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Linear equation

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For an equation to be meaningful, the coefficient of at least one variable must be non-zero. If every variable has a zero coefficient, then, as mentioned for one variable, the equation is either
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in the Euclidean plane, and, conversely, every line can be viewed as the set of all solutions of a linear equation in two variables. This is the origin of the term
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A line that is not parallel to an axis and does not pass through the origin cuts the axes into two different points. The intercept values
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is a function that maps a sum to the sum of the images of the summands. So, for this definition, the above function is linear only when
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Besides being very simple and mnemonic, this form has the advantage of being a special case of the more general equation of a
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There are various ways of defining a line. In the following subsections, a linear equation of the line is given in each case.
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This form is not symmetric in the two given points, but a symmetric form can be obtained by regrouping the constant terms:
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if the coefficients are complex numbers or belong to any field). In the case of three variables, this hyperplane is a
1996:, there is exactly one line that passes through them. There are several ways to write a linear equation of this line. 3837: 654: 441: 3790: 3982: 257: 3921: 3044:{\displaystyle {\begin{vmatrix}x&y&1\\x_{1}&y_{1}&1\\x_{2}&y_{2}&1\end{vmatrix}}=0.} 195: 3951: 3946: 3941: 3819: 3545:{\displaystyle x_{j}=-{\frac {b}{a_{j}}}-\sum _{i\in \{1,\ldots ,n\},i\neq j}{\frac {a_{i}}{a_{j}}}x_{i}.} 790: 185: 1644: 263: 141: 3931: 3911: 3354: 2211: 1781: 1714: 1146: 1082: 1020: 372: 189: 526: 843: 260:, provided they do not contain any of the variables. To yield a meaningful equation, the coefficients 3997: 3916: 3783: 3758: 3560: 807: 1042:
The phrase "linear equation" takes its origin in this correspondence between lines and equations: a
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of such an equation are the values that, when substituted for the unknowns, make the equality true.
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for emphasizing that the slope of a line can be computed from the coordinates of any two points.
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are not both zero. Conversely, every line is the set of all solutions of a linear equation.
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for describing this type of equation. More generally, the solutions of a linear equation in
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can be obtained by expanding with respect to its first row the determinant in the equation
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solutions and, more generally, to linear equations with coefficients and solutions in any
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This article considers the case of a single equation with coefficients from the field of
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refers implicitly to this particular case, in which the variable is sensibly called the
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A linear equation with more than two variables may always be assumed to have the form
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The two-point form of the equation of a line can be expressed simply in terms of a
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College Mathematics for Business, Economics, Life Sciences and the Social Sciences
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If, moreover, the line is not horizontal, it can be defined by its slope and its
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Linear equations occur frequently in all mathematics and their applications in
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In the case of just one variable, there is exactly one solution (provided that
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of any point of the line. In this case, a linear equation of the line is
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These forms rely on the habit of considering a nonvertical line as the
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Alternatively, a linear equation can be obtained by equating to zero a
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In the case of two variables, each solution may be interpreted as the
2200:{\displaystyle y-y_{1}={\frac {y_{2}-y_{1}}{x_{2}-x_{1}}}(x-x_{1}).} 940: 939: 923: 922: 1934:(It is easy to verify that the line defined by this equation has 1027:. With this interpretation, all solutions of the equation form a 2341:{\displaystyle (x_{2}-x_{1})(y-y_{1})-(y_{2}-y_{1})(x-x_{1})=0,} 1868:
of these two points are nonzero, and an equation of the line is
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Equation that does not involve powers or products of variables
3182:{\displaystyle a_{1}x_{1}+a_{2}x_{2}+\cdots +a_{n}x_{n}+b=0.} 1046:
in two variables is an equation whose solutions form a line.
440:. For the case of several simultaneous linear equations, see 2661:
is the result of expanding the determinant in the equation
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The functions whose graph is a line are generally called
1924:{\displaystyle {\frac {x}{x_{0}}}+{\frac {y}{y_{0}}}=1.} 2949: 2676: 1458:
these forms can be easily deduced from the relations
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are real numbers, it has infinitely many solutions.
3965: 3904: 3817: 3702:Barnett, R.A.; Ziegler, M.R.; Byleen, K.E. (2008), 3346:-tuples that are solutions of a linear equation in 2082:{\displaystyle {\frac {y_{2}-y_{1}}{x_{2}-x_{1}}}.} 1064:that has been defined in the preceding section. If 3721: 3544: 3303: 3283: 3256: 3213:in old books). Depending on the context, the term 3181: 3043: 2926: 2781: 2653: 2507: 2340: 2199: 2081: 1923: 1831: 1764: 1697: 1630: 1578: 1447: 1390: 1336: 1266: 1174: 1110: 1008: 865: 826: 779:{\displaystyle y=-{\frac {a}{b}}x-{\frac {c}{b}}.} 778: 705: 614: 551: 512: 486: 352: 298: 236: 176: 131:{\displaystyle a_{1}x_{1}+\ldots +a_{n}x_{n}+b=0,} 130: 425:are often well approximated by linear equations. 1594:A non-vertical line can be defined by its slope 1197:A non-vertical line can be defined by its slope 1193:Slope–intercept form or Gradient-intercept form 3630: 41:Two graphs of linear equations in two variables 3828:Zero polynomial (degree undefined or −1 or −∞) 3641: 3639: 3791: 8: 3645: 3488: 3470: 1290:. In this case, its equation can be written 716:is a linear equation in the single variable 379:. The solutions of a linear equation form a 3661:An Elementary Course in Theory of Equations 3069:. These equations rely on the condition of 3798: 3784: 3776: 3681:Numbers Universalized: An Advanced Algebra 3277: 3533: 3521: 3511: 3505: 3463: 3448: 3439: 3427: 3421: 3296: 3269: 3243: 3161: 3151: 3132: 3122: 3109: 3099: 3093: 3016: 3004: 2985: 2973: 2944: 2942: 2909: 2899: 2886: 2876: 2854: 2841: 2819: 2806: 2797: 2759: 2746: 2734: 2721: 2707: 2689: 2671: 2669: 2636: 2614: 2601: 2582: 2560: 2547: 2538: 2490: 2480: 2467: 2457: 2435: 2422: 2400: 2387: 2378: 2320: 2298: 2285: 2266: 2244: 2231: 2222: 2185: 2163: 2150: 2138: 2125: 2118: 2109: 2097: 2067: 2054: 2042: 2029: 2022: 2020: 1907: 1898: 1887: 1878: 1876: 1820: 1795: 1783: 1753: 1737: 1716: 1683: 1658: 1646: 1622: 1609: 1603: 1559: 1543: 1522: 1506: 1485: 1468: 1466: 1413: 1379: 1355: 1322: 1298: 1255: 1234: 1159: 1148: 1132:, the line is the graph of a function of 1095: 1084: 977: 850: 845: 814: 809: 763: 747: 736: 724:. It has therefore a unique solution for 674: 580: 539: 528: 499: 461: 338: 332: 317:, from which the coefficients are taken. 290: 271: 265: 228: 209: 197: 168: 149: 143: 107: 97: 78: 68: 62: 1218:coordinate of its intersection with the 1143:, one has a horizontal line of equation 1118:which is not the graph of a function of 252:. The coefficients may be considered as 36: 3720:Larson, Ron; Hostetler, Robert (2007), 3611: 1590:Point–slope form or Point-gradient form 3402:, then the equation can be solved for 2530:. There are two common ways for that. 3684:. American Book Company. p. 113. 902:, and the linear functions such that 256:of the equation and may be arbitrary 237:{\displaystyle b,a_{1},\ldots ,a_{n}} 7: 3314:A solution of such an equation is a 3742:Wilson, W.A.; Tracey, J.I. (1925), 3390:If a linear equation is given with 1698:{\displaystyle y=y_{1}+m(x-x_{1}),} 1405:. For a line given by an equation 567:A linear equation in two variables 299:{\displaystyle a_{1},\ldots ,a_{n}} 177:{\displaystyle x_{1},\ldots ,x_{n}} 3664:. J. Wiley & sons. p. 17. 3619:Barnett, Ziegler & Byleen 2008 1832:{\displaystyle y-y_{1}=m(x-x_{1})} 1775:This equation can also be written 1765:{\displaystyle y=mx+y_{1}-mx_{1}.} 1175:{\displaystyle y=-{\frac {c}{b}}.} 1111:{\displaystyle x=-{\frac {c}{a}},} 452:A linear equation in one variable 25: 552:{\displaystyle x=-{\frac {b}{a}}} 306:are required to not all be zero. 3332:) as having no solution, or all 1075:(that is a line parallel to the 866:{\displaystyle -{\frac {c}{b}}.} 3264:variables, it is common to use 3062:points in a space of dimension 827:{\displaystyle -{\frac {a}{b}}} 3746:(revised ed.), D.C. Heath 3678:David Martin Sensenig (1890). 3658:Charles Hiram Chapman (1892). 3311:instead of indexed variables. 2915: 2869: 2860: 2834: 2825: 2799: 2642: 2623: 2620: 2594: 2588: 2569: 2566: 2540: 2496: 2450: 2441: 2415: 2406: 2380: 2326: 2307: 2304: 2278: 2272: 2253: 2250: 2224: 2191: 2172: 1826: 1807: 1689: 1670: 1328: 1309: 1: 3988:Horner's method of evaluation 1337:{\displaystyle y=m(x-x_{0}),} 3724:Precalculus:A Concise Course 2089:Thus, a point-slope form is 1391:{\displaystyle y=mx-mx_{0}.} 944:Horizontal line of equation 57:that may be put in the form 32:Linear differential equation 3993:Polynomial identity testing 3764:Encyclopedia of Mathematics 3631:Larson & Hostetler 2007 3580:Linear equation over a ring 2015:, the slope of the line is 1960:Given two different points 1631:{\displaystyle x_{1},y_{1}} 1267:{\displaystyle y=mx+y_{0}.} 353:{\displaystyle a_{1}\neq 0} 4050: 1448:{\displaystyle ax+by+c=0,} 1222:-axis). In this case, its 927:Vertical line of equation 655:Linear function (calculus) 652: 615:{\displaystyle ax+by+c=0,} 442:system of linear equations 29: 2351:which is valid also when 2214:, one gets the equation 1009:{\displaystyle ax+by+c=0} 706:{\displaystyle ax+by+c=0} 395:(a subspace of dimension 3646:Wilson & Tracey 1925 3555:If the coefficients are 3217:can be reserved for the 919:Geometric interpretation 30:Not to be confused with 3978:Greatest common divisor 3081:More than two variables 513:{\displaystyle a\neq 0} 487:{\displaystyle ax+b=0,} 3850:Quadratic function (2) 3546: 3305: 3285: 3258: 3183: 3045: 2928: 2783: 2655: 2509: 2342: 2201: 2083: 1952:as intercept values). 1925: 1833: 1766: 1699: 1632: 1598:, and the coordinates 1580: 1449: 1392: 1338: 1268: 1176: 1112: 1010: 954: 937: 867: 828: 797:of this function is a 780: 707: 616: 553: 514: 488: 354: 300: 238: 178: 132: 42: 3833:Constant function (0) 3547: 3355:Cartesian coordinates 3306: 3286: 3284:{\displaystyle x,\;y} 3259: 3184: 3046: 2929: 2784: 2656: 2510: 2343: 2212:clearing denominators 2202: 2084: 1926: 1834: 1767: 1700: 1633: 1581: 1450: 1393: 1339: 1269: 1177: 1113: 1058:graph of the function 1021:Cartesian coordinates 1019:may be viewed as the 1011: 969:of a linear equation 943: 926: 868: 829: 781: 728:, which is given by 708: 617: 554: 515: 489: 373:Cartesian coordinates 355: 301: 239: 179: 133: 40: 3966:Tools and algorithms 3886:Quintic function (5) 3874:Quartic function (4) 3811:polynomial functions 3728:, Houghton Mifflin, 3420: 3357:of the points of an 3295: 3268: 3242: 3092: 2941: 2796: 2668: 2537: 2377: 2221: 2096: 2019: 1875: 1782: 1715: 1645: 1602: 1465: 1412: 1354: 1297: 1233: 1147: 1083: 976: 844: 808: 735: 673: 579: 527: 498: 460: 331: 264: 196: 142: 61: 3896:Septic equation (7) 3891:Sextic equation (6) 3838:Linear function (1) 3687:Extract of page 113 3257:{\displaystyle n=3} 1403:graph of a function 1079:-axis) of equation 720:for every value of 360:). Often, the term 4029:Elementary algebra 3862:Cubic function (3) 3855:Quadratic equation 3667:Extract of page 17 3600:Nonlinear equation 3585:Algebraic equation 3542: 3504: 3301: 3281: 3254: 3238:When dealing with 3179: 3041: 3029: 2924: 2779: 2767: 2651: 2505: 2338: 2197: 2079: 1921: 1829: 1762: 1695: 1628: 1576: 1574: 1445: 1388: 1347:or, equivalently, 1334: 1264: 1185:Equation of a line 1172: 1108: 1056:, the line is the 1023:of a point in the 1006: 955: 938: 877:in the context of 863: 824: 776: 703: 612: 575:can be written as 549: 510: 484: 456:can be written as 423:non-linear systems 375:of a point of the 350: 296: 248:, which are often 234: 174: 128: 43: 4016: 4015: 3957:Quasi-homogeneous 3759:"Linear equation" 3744:Analytic Geometry 3735:978-0-618-62719-6 3713:978-0-13-157225-6 3595:Linear inequality 3559:, this defines a 3527: 3459: 3454: 3304:{\displaystyle z} 3071:linear dependence 2170: 2074: 1913: 1893: 1567: 1530: 1493: 1167: 1103: 909:are often called 858: 822: 771: 755: 547: 421:, partly because 391:variables form a 311:linear polynomial 16:(Redirected from 4041: 3879:Quartic equation 3800: 3793: 3786: 3777: 3772: 3747: 3738: 3727: 3716: 3689: 3685: 3675: 3669: 3665: 3655: 3649: 3643: 3634: 3628: 3622: 3616: 3590:Line coordinates 3567: 3551: 3549: 3548: 3543: 3538: 3537: 3528: 3526: 3525: 3516: 3515: 3506: 3503: 3455: 3453: 3452: 3440: 3432: 3431: 3412: 3401: 3375: 3373: 3364: 3352: 3350: 3345: 3338: 3336: 3331: 3317: 3310: 3308: 3307: 3302: 3290: 3288: 3287: 3282: 3263: 3261: 3260: 3255: 3234: 3227: 3204: 3196:, often denoted 3195: 3192:The coefficient 3188: 3186: 3185: 3180: 3166: 3165: 3156: 3155: 3137: 3136: 3127: 3126: 3114: 3113: 3104: 3103: 3075:projective space 3068: 3061: 3058:passing through 3050: 3048: 3047: 3042: 3034: 3033: 3021: 3020: 3009: 3008: 2990: 2989: 2978: 2977: 2933: 2931: 2930: 2925: 2914: 2913: 2904: 2903: 2891: 2890: 2881: 2880: 2859: 2858: 2846: 2845: 2824: 2823: 2811: 2810: 2788: 2786: 2785: 2780: 2772: 2771: 2764: 2763: 2751: 2750: 2739: 2738: 2726: 2725: 2712: 2711: 2694: 2693: 2660: 2658: 2657: 2652: 2641: 2640: 2619: 2618: 2606: 2605: 2587: 2586: 2565: 2564: 2552: 2551: 2522:Determinant form 2514: 2512: 2511: 2506: 2495: 2494: 2485: 2484: 2472: 2471: 2462: 2461: 2440: 2439: 2427: 2426: 2405: 2404: 2392: 2391: 2366: 2347: 2345: 2344: 2339: 2325: 2324: 2303: 2302: 2290: 2289: 2271: 2270: 2249: 2248: 2236: 2235: 2206: 2204: 2203: 2198: 2190: 2189: 2171: 2169: 2168: 2167: 2155: 2154: 2144: 2143: 2142: 2130: 2129: 2119: 2114: 2113: 2088: 2086: 2085: 2080: 2075: 2073: 2072: 2071: 2059: 2058: 2048: 2047: 2046: 2034: 2033: 2023: 2014: 1995: 1977: 1951: 1942: 1930: 1928: 1927: 1922: 1914: 1912: 1911: 1899: 1894: 1892: 1891: 1879: 1867: 1858: 1838: 1836: 1835: 1830: 1825: 1824: 1800: 1799: 1771: 1769: 1768: 1763: 1758: 1757: 1742: 1741: 1704: 1702: 1701: 1696: 1688: 1687: 1663: 1662: 1637: 1635: 1634: 1629: 1627: 1626: 1614: 1613: 1597: 1585: 1583: 1582: 1577: 1575: 1568: 1560: 1548: 1547: 1531: 1523: 1511: 1510: 1494: 1486: 1454: 1452: 1451: 1446: 1397: 1395: 1394: 1389: 1384: 1383: 1343: 1341: 1340: 1335: 1327: 1326: 1289: 1280: 1273: 1271: 1270: 1265: 1260: 1259: 1226:can be written 1221: 1217: 1213: 1204: 1200: 1181: 1179: 1178: 1173: 1168: 1160: 1142: 1135: 1131: 1121: 1117: 1115: 1114: 1109: 1104: 1096: 1078: 1071:, the line is a 1070: 1063: 1055: 1038: 1034: 1031:, provided that 1015: 1013: 1012: 1007: 968: 953: 936: 908: 899:affine functions 895: 875:linear functions 872: 870: 869: 864: 859: 851: 838: 833: 831: 830: 825: 823: 815: 785: 783: 782: 777: 772: 764: 756: 748: 727: 723: 719: 712: 710: 709: 704: 666:, the equation 665: 644: 640: 633: 629: 625: 621: 619: 618: 613: 574: 570: 558: 556: 555: 550: 548: 540: 523:The solution is 519: 517: 516: 511: 493: 491: 490: 485: 455: 409: 401: 390: 359: 357: 356: 351: 343: 342: 305: 303: 302: 297: 295: 294: 276: 275: 243: 241: 240: 235: 233: 232: 214: 213: 183: 181: 180: 175: 173: 172: 154: 153: 137: 135: 134: 129: 112: 111: 102: 101: 83: 82: 73: 72: 21: 18:Linear equations 4049: 4048: 4044: 4043: 4042: 4040: 4039: 4038: 4019: 4018: 4017: 4012: 3961: 3900: 3843:Linear equation 3813: 3804: 3757: 3754: 3741: 3736: 3719: 3714: 3701: 3698: 3693: 3692: 3677: 3676: 3672: 3657: 3656: 3652: 3644: 3637: 3629: 3625: 3617: 3613: 3608: 3576: 3565: 3529: 3517: 3507: 3444: 3423: 3418: 3417: 3411: 3403: 3399: 3391: 3377:Euclidean space 3371: 3370: 3358: 3348: 3347: 3343: 3339:are solutions. 3334: 3333: 3326: 3315: 3293: 3292: 3266: 3265: 3240: 3239: 3229: 3226: 3218: 3209:(sometimes the 3203: 3197: 3193: 3157: 3147: 3128: 3118: 3105: 3095: 3090: 3089: 3083: 3073:of points in a 3063: 3059: 3028: 3027: 3022: 3012: 3010: 3000: 2997: 2996: 2991: 2981: 2979: 2969: 2966: 2965: 2960: 2955: 2945: 2939: 2938: 2905: 2895: 2882: 2872: 2850: 2837: 2815: 2802: 2794: 2793: 2766: 2765: 2755: 2742: 2740: 2730: 2717: 2714: 2713: 2703: 2695: 2685: 2672: 2666: 2665: 2632: 2610: 2597: 2578: 2556: 2543: 2535: 2534: 2524: 2486: 2476: 2463: 2453: 2431: 2418: 2396: 2383: 2375: 2374: 2365: 2358: 2352: 2316: 2294: 2281: 2262: 2240: 2227: 2219: 2218: 2181: 2159: 2146: 2145: 2134: 2121: 2120: 2105: 2094: 2093: 2063: 2050: 2049: 2038: 2025: 2024: 2017: 2016: 2013: 2006: 2000: 1993: 1986: 1979: 1975: 1968: 1961: 1958: 1950: 1944: 1941: 1935: 1903: 1883: 1873: 1872: 1866: 1860: 1857: 1851: 1848: 1816: 1791: 1780: 1779: 1749: 1733: 1713: 1712: 1679: 1654: 1643: 1642: 1618: 1605: 1600: 1599: 1595: 1592: 1573: 1572: 1549: 1539: 1536: 1535: 1512: 1502: 1499: 1498: 1475: 1463: 1462: 1410: 1409: 1375: 1352: 1351: 1318: 1295: 1294: 1288: 1282: 1278: 1251: 1231: 1230: 1224:linear equation 1219: 1215: 1212: 1206: 1202: 1198: 1195: 1187: 1145: 1144: 1137: 1133: 1126: 1119: 1081: 1080: 1076: 1065: 1061: 1050: 1044:linear equation 1036: 1032: 1025:Euclidean plane 974: 973: 958: 945: 928: 921: 903: 890: 887:linear function 842: 841: 836: 806: 805: 789:This defines a 733: 732: 725: 721: 717: 671: 670: 660: 657: 651: 649:Linear function 642: 638: 631: 627: 623: 577: 576: 572: 568: 565: 525: 524: 496: 495: 458: 457: 453: 450: 407: 404:Euclidean space 396: 388: 377:Euclidean plane 362:linear equation 334: 329: 328: 286: 267: 262: 261: 224: 205: 194: 193: 164: 145: 140: 139: 103: 93: 74: 64: 59: 58: 51:linear equation 35: 28: 23: 22: 15: 12: 11: 5: 4047: 4045: 4037: 4036: 4031: 4021: 4020: 4014: 4013: 4011: 4010: 4005: 4000: 3995: 3990: 3985: 3980: 3975: 3969: 3967: 3963: 3962: 3960: 3959: 3954: 3949: 3944: 3939: 3934: 3929: 3924: 3919: 3914: 3908: 3906: 3902: 3901: 3899: 3898: 3893: 3888: 3883: 3882: 3881: 3871: 3870: 3869: 3867:Cubic equation 3859: 3858: 3857: 3847: 3846: 3845: 3835: 3830: 3824: 3822: 3815: 3814: 3805: 3803: 3802: 3795: 3788: 3780: 3774: 3773: 3753: 3752:External links 3750: 3749: 3748: 3739: 3734: 3717: 3712: 3697: 3694: 3691: 3690: 3670: 3650: 3635: 3623: 3610: 3609: 3607: 3604: 3603: 3602: 3597: 3592: 3587: 3582: 3575: 3572: 3568:real variables 3553: 3552: 3541: 3536: 3532: 3524: 3520: 3514: 3510: 3502: 3499: 3496: 3493: 3490: 3487: 3484: 3481: 3478: 3475: 3472: 3469: 3466: 3462: 3458: 3451: 3447: 3443: 3438: 3435: 3430: 3426: 3407: 3395: 3300: 3280: 3276: 3273: 3253: 3250: 3247: 3222: 3205:is called the 3201: 3190: 3189: 3178: 3175: 3172: 3169: 3164: 3160: 3154: 3150: 3146: 3143: 3140: 3135: 3131: 3125: 3121: 3117: 3112: 3108: 3102: 3098: 3082: 3079: 3052: 3051: 3040: 3037: 3032: 3026: 3023: 3019: 3015: 3011: 3007: 3003: 2999: 2998: 2995: 2992: 2988: 2984: 2980: 2976: 2972: 2968: 2967: 2964: 2961: 2959: 2956: 2954: 2951: 2950: 2948: 2923: 2920: 2917: 2912: 2908: 2902: 2898: 2894: 2889: 2885: 2879: 2875: 2871: 2868: 2865: 2862: 2857: 2853: 2849: 2844: 2840: 2836: 2833: 2830: 2827: 2822: 2818: 2814: 2809: 2805: 2801: 2790: 2789: 2778: 2775: 2770: 2762: 2758: 2754: 2749: 2745: 2741: 2737: 2733: 2729: 2724: 2720: 2716: 2715: 2710: 2706: 2702: 2699: 2696: 2692: 2688: 2684: 2681: 2678: 2677: 2675: 2650: 2647: 2644: 2639: 2635: 2631: 2628: 2625: 2622: 2617: 2613: 2609: 2604: 2600: 2596: 2593: 2590: 2585: 2581: 2577: 2574: 2571: 2568: 2563: 2559: 2555: 2550: 2546: 2542: 2523: 2520: 2516: 2515: 2504: 2501: 2498: 2493: 2489: 2483: 2479: 2475: 2470: 2466: 2460: 2456: 2452: 2449: 2446: 2443: 2438: 2434: 2430: 2425: 2421: 2417: 2414: 2411: 2408: 2403: 2399: 2395: 2390: 2386: 2382: 2363: 2356: 2349: 2348: 2337: 2334: 2331: 2328: 2323: 2319: 2315: 2312: 2309: 2306: 2301: 2297: 2293: 2288: 2284: 2280: 2277: 2274: 2269: 2265: 2261: 2258: 2255: 2252: 2247: 2243: 2239: 2234: 2230: 2226: 2208: 2207: 2196: 2193: 2188: 2184: 2180: 2177: 2174: 2166: 2162: 2158: 2153: 2149: 2141: 2137: 2133: 2128: 2124: 2117: 2112: 2108: 2104: 2101: 2078: 2070: 2066: 2062: 2057: 2053: 2045: 2041: 2037: 2032: 2028: 2011: 2004: 1991: 1984: 1973: 1966: 1957: 1956:Two-point form 1954: 1948: 1939: 1932: 1931: 1920: 1917: 1910: 1906: 1902: 1897: 1890: 1886: 1882: 1864: 1855: 1847: 1846:Intercept form 1844: 1840: 1839: 1828: 1823: 1819: 1815: 1812: 1809: 1806: 1803: 1798: 1794: 1790: 1787: 1773: 1772: 1761: 1756: 1752: 1748: 1745: 1740: 1736: 1732: 1729: 1726: 1723: 1720: 1706: 1705: 1694: 1691: 1686: 1682: 1678: 1675: 1672: 1669: 1666: 1661: 1657: 1653: 1650: 1625: 1621: 1617: 1612: 1608: 1591: 1588: 1587: 1586: 1571: 1566: 1563: 1558: 1555: 1552: 1550: 1546: 1542: 1538: 1537: 1534: 1529: 1526: 1521: 1518: 1515: 1513: 1509: 1505: 1501: 1500: 1497: 1492: 1489: 1484: 1481: 1478: 1476: 1474: 1471: 1470: 1456: 1455: 1444: 1441: 1438: 1435: 1432: 1429: 1426: 1423: 1420: 1417: 1399: 1398: 1387: 1382: 1378: 1374: 1371: 1368: 1365: 1362: 1359: 1345: 1344: 1333: 1330: 1325: 1321: 1317: 1314: 1311: 1308: 1305: 1302: 1286: 1275: 1274: 1263: 1258: 1254: 1250: 1247: 1244: 1241: 1238: 1210: 1194: 1191: 1186: 1183: 1171: 1166: 1163: 1158: 1155: 1152: 1125:Similarly, if 1107: 1102: 1099: 1094: 1091: 1088: 1017: 1016: 1005: 1002: 999: 996: 993: 990: 987: 984: 981: 957:Each solution 920: 917: 883:linear algebra 881:. However, in 862: 857: 854: 849: 821: 818: 813: 787: 786: 775: 770: 767: 762: 759: 754: 751: 746: 743: 740: 714: 713: 702: 699: 696: 693: 690: 687: 684: 681: 678: 653:Main article: 650: 647: 611: 608: 605: 602: 599: 596: 593: 590: 587: 584: 564: 561: 546: 543: 538: 535: 532: 509: 506: 503: 483: 480: 477: 474: 471: 468: 465: 449: 446: 349: 346: 341: 337: 293: 289: 285: 282: 279: 274: 270: 231: 227: 223: 220: 217: 212: 208: 204: 201: 171: 167: 163: 160: 157: 152: 148: 127: 124: 121: 118: 115: 110: 106: 100: 96: 92: 89: 86: 81: 77: 71: 67: 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 4046: 4035: 4032: 4030: 4027: 4026: 4024: 4009: 4008:Gröbner basis 4006: 4004: 4001: 3999: 3996: 3994: 3991: 3989: 3986: 3984: 3981: 3979: 3976: 3974: 3973:Factorization 3971: 3970: 3968: 3964: 3958: 3955: 3953: 3950: 3948: 3945: 3943: 3940: 3938: 3935: 3933: 3930: 3928: 3925: 3923: 3920: 3918: 3915: 3913: 3910: 3909: 3907: 3905:By properties 3903: 3897: 3894: 3892: 3889: 3887: 3884: 3880: 3877: 3876: 3875: 3872: 3868: 3865: 3864: 3863: 3860: 3856: 3853: 3852: 3851: 3848: 3844: 3841: 3840: 3839: 3836: 3834: 3831: 3829: 3826: 3825: 3823: 3821: 3816: 3812: 3808: 3801: 3796: 3794: 3789: 3787: 3782: 3781: 3778: 3770: 3766: 3765: 3760: 3756: 3755: 3751: 3745: 3740: 3737: 3731: 3726: 3725: 3718: 3715: 3709: 3705: 3700: 3699: 3695: 3688: 3683: 3682: 3674: 3671: 3668: 3663: 3662: 3654: 3651: 3647: 3642: 3640: 3636: 3632: 3627: 3624: 3620: 3615: 3612: 3605: 3601: 3598: 3596: 3593: 3591: 3588: 3586: 3583: 3581: 3578: 3577: 3573: 3571: 3569: 3562: 3558: 3539: 3534: 3530: 3522: 3518: 3512: 3508: 3500: 3497: 3494: 3491: 3485: 3482: 3479: 3476: 3473: 3467: 3464: 3460: 3456: 3449: 3445: 3441: 3436: 3433: 3428: 3424: 3416: 3415: 3414: 3410: 3406: 3398: 3394: 3388: 3386: 3382: 3378: 3368: 3365:-dimensional 3362: 3356: 3340: 3329: 3324: 3319: 3312: 3298: 3278: 3274: 3271: 3251: 3248: 3245: 3236: 3232: 3225: 3221: 3216: 3212: 3211:absolute term 3208: 3207:constant term 3200: 3176: 3173: 3170: 3167: 3162: 3158: 3152: 3148: 3144: 3141: 3138: 3133: 3129: 3123: 3119: 3115: 3110: 3106: 3100: 3096: 3088: 3087: 3086: 3080: 3078: 3076: 3072: 3066: 3057: 3038: 3035: 3030: 3024: 3017: 3013: 3005: 3001: 2993: 2986: 2982: 2974: 2970: 2962: 2957: 2952: 2946: 2937: 2936: 2935: 2921: 2918: 2910: 2906: 2900: 2896: 2892: 2887: 2883: 2877: 2873: 2866: 2863: 2855: 2851: 2847: 2842: 2838: 2831: 2828: 2820: 2816: 2812: 2807: 2803: 2792:The equation 2776: 2773: 2768: 2760: 2756: 2752: 2747: 2743: 2735: 2731: 2727: 2722: 2718: 2708: 2704: 2700: 2697: 2690: 2686: 2682: 2679: 2673: 2664: 2663: 2662: 2648: 2645: 2637: 2633: 2629: 2626: 2615: 2611: 2607: 2602: 2598: 2591: 2583: 2579: 2575: 2572: 2561: 2557: 2553: 2548: 2544: 2533:The equation 2531: 2529: 2521: 2519: 2502: 2499: 2491: 2487: 2481: 2477: 2473: 2468: 2464: 2458: 2454: 2447: 2444: 2436: 2432: 2428: 2423: 2419: 2412: 2409: 2401: 2397: 2393: 2388: 2384: 2373: 2372: 2371: 2368: 2362: 2355: 2335: 2332: 2329: 2321: 2317: 2313: 2310: 2299: 2295: 2291: 2286: 2282: 2275: 2267: 2263: 2259: 2256: 2245: 2241: 2237: 2232: 2228: 2217: 2216: 2215: 2213: 2194: 2186: 2182: 2178: 2175: 2164: 2160: 2156: 2151: 2147: 2139: 2135: 2131: 2126: 2122: 2115: 2110: 2106: 2102: 2099: 2092: 2091: 2090: 2076: 2068: 2064: 2060: 2055: 2051: 2043: 2039: 2035: 2030: 2026: 2010: 2003: 1997: 1990: 1983: 1972: 1965: 1955: 1953: 1947: 1938: 1918: 1915: 1908: 1904: 1900: 1895: 1888: 1884: 1880: 1871: 1870: 1869: 1863: 1854: 1845: 1843: 1821: 1817: 1813: 1810: 1804: 1801: 1796: 1792: 1788: 1785: 1778: 1777: 1776: 1759: 1754: 1750: 1746: 1743: 1738: 1734: 1730: 1727: 1724: 1721: 1718: 1711: 1710: 1709: 1692: 1684: 1680: 1676: 1673: 1667: 1664: 1659: 1655: 1651: 1648: 1641: 1640: 1639: 1623: 1619: 1615: 1610: 1606: 1589: 1569: 1564: 1561: 1556: 1553: 1551: 1544: 1540: 1532: 1527: 1524: 1519: 1516: 1514: 1507: 1503: 1495: 1490: 1487: 1482: 1479: 1477: 1472: 1461: 1460: 1459: 1442: 1439: 1436: 1433: 1430: 1427: 1424: 1421: 1418: 1415: 1408: 1407: 1406: 1404: 1385: 1380: 1376: 1372: 1369: 1366: 1363: 1360: 1357: 1350: 1349: 1348: 1331: 1323: 1319: 1315: 1312: 1306: 1303: 1300: 1293: 1292: 1291: 1285: 1261: 1256: 1252: 1248: 1245: 1242: 1239: 1236: 1229: 1228: 1227: 1225: 1209: 1192: 1190: 1184: 1182: 1169: 1164: 1161: 1156: 1153: 1150: 1140: 1129: 1123: 1105: 1100: 1097: 1092: 1089: 1086: 1074: 1073:vertical line 1068: 1059: 1053: 1047: 1045: 1040: 1030: 1026: 1022: 1003: 1000: 997: 994: 991: 988: 985: 982: 979: 972: 971: 970: 966: 962: 952: 948: 942: 935: 931: 925: 918: 916: 914: 913: 906: 901: 900: 893: 888: 884: 880: 876: 860: 855: 852: 847: 840: 819: 816: 811: 804: 800: 796: 792: 773: 768: 765: 760: 757: 752: 749: 744: 741: 738: 731: 730: 729: 700: 697: 694: 691: 688: 685: 682: 679: 676: 669: 668: 667: 663: 656: 648: 646: 635: 609: 606: 603: 600: 597: 594: 591: 588: 585: 582: 563:Two variables 562: 560: 544: 541: 536: 533: 530: 521: 507: 504: 501: 481: 478: 475: 472: 469: 466: 463: 447: 445: 443: 439: 435: 431: 426: 424: 420: 416: 411: 406:of dimension 405: 399: 394: 386: 382: 378: 374: 369: 367: 363: 347: 344: 339: 335: 325: 323: 318: 316: 312: 307: 291: 287: 283: 280: 277: 272: 268: 259: 255: 251: 247: 229: 225: 221: 218: 215: 210: 206: 202: 199: 191: 187: 169: 165: 161: 158: 155: 150: 146: 125: 122: 119: 116: 113: 108: 104: 98: 94: 90: 87: 84: 79: 75: 69: 65: 56: 52: 48: 39: 33: 19: 4003:Discriminant 3922:Multivariate 3842: 3762: 3743: 3723: 3703: 3680: 3673: 3660: 3653: 3626: 3614: 3564:function of 3557:real numbers 3554: 3413:, yielding 3408: 3404: 3396: 3392: 3389: 3381:affine space 3374:-dimensional 3360: 3341: 3327: 3323:inconsistent 3322: 3320: 3313: 3237: 3230: 3223: 3219: 3214: 3210: 3206: 3198: 3191: 3084: 3064: 3053: 2791: 2532: 2525: 2517: 2369: 2360: 2353: 2350: 2209: 2008: 2001: 1998: 1988: 1981: 1970: 1963: 1959: 1945: 1936: 1933: 1861: 1852: 1849: 1841: 1774: 1707: 1593: 1457: 1400: 1346: 1283: 1276: 1223: 1207: 1196: 1188: 1138: 1127: 1124: 1072: 1066: 1051: 1048: 1043: 1041: 1018: 964: 960: 956: 950: 946: 933: 929: 910: 904: 897: 891: 874: 788: 715: 661: 658: 636: 566: 522: 451: 448:One variable 430:real numbers 427: 412: 397: 384: 370: 365: 361: 326: 319: 308: 250:real numbers 246:coefficients 50: 44: 3952:Homogeneous 3947:Square-free 3942:Irreducible 3807:Polynomials 3648:, pp. 52-53 3561:real-valued 3215:coefficient 2528:determinant 1281:-intercept 1205:-intercept 912:linear maps 419:engineering 258:expressions 47:mathematics 4023:Categories 3912:Univariate 3696:References 3367:hyperplane 3056:hyperplane 1201:, and its 1136:, and, if 839:-intercept 393:hyperplane 313:over some 254:parameters 4034:Equations 3998:Resultant 3937:Trinomial 3917:Bivariate 3769:EMS Press 3498:≠ 3480:… 3468:∈ 3461:∑ 3457:− 3437:− 3351:variables 3142:⋯ 2893:− 2848:− 2813:− 2753:− 2728:− 2701:− 2683:− 2630:− 2608:− 2592:− 2576:− 2554:− 2474:− 2429:− 2394:− 2314:− 2292:− 2276:− 2260:− 2238:− 2179:− 2157:− 2132:− 2103:− 2061:− 2036:− 1814:− 1789:− 1744:− 1677:− 1557:− 1520:− 1483:− 1370:− 1316:− 1157:− 1093:− 848:− 812:− 761:− 745:− 630:not both 537:− 505:≠ 402:) in the 345:≠ 322:solutions 281:… 219:… 186:variables 159:… 88:… 3983:Division 3932:Binomial 3927:Monomial 3621:, pg. 15 3574:See also 3353:are the 879:calculus 791:function 244:are the 190:unknowns 184:are the 55:equation 3771:, 2001 3633:, p. 25 3337:-tuples 434:complex 415:physics 366:unknown 192:), and 3820:degree 3732:  3710:  3369:in an 3233:> 0 793:. The 385:linear 138:where 53:is an 3606:Notes 3385:plane 3325:(for 3228:with 1214:(the 803:slope 801:with 795:graph 626:and 622:with 494:with 438:field 315:field 3809:and 3730:ISBN 3708:ISBN 3379:(or 3363:− 1) 3342:The 3291:and 1978:and 1943:and 1859:and 1708:or 1035:and 1029:line 885:, a 834:and 799:line 641:and 571:and 417:and 381:line 320:The 188:(or 49:, a 3818:By 3400:≠ 0 3330:≠ 0 3067:– 1 2210:By 1999:If 1141:= 0 1130:≠ 0 1069:= 0 1060:of 1054:≠ 0 1049:If 907:= 0 894:= 0 664:≠ 0 659:If 637:If 520:. 400:− 1 45:In 4025:: 3767:, 3761:, 3638:^ 3570:. 3387:. 3235:. 3177:0. 3077:. 3039:0. 2777:0. 2359:= 2007:≠ 1987:, 1969:, 1919:1. 1122:. 963:, 949:= 932:= 915:. 634:. 559:. 444:. 410:. 368:. 3799:e 3792:t 3785:v 3566:n 3540:. 3535:i 3531:x 3523:j 3519:a 3513:i 3509:a 3501:j 3495:i 3492:, 3489:} 3486:n 3483:, 3477:, 3474:1 3471:{ 3465:i 3450:j 3446:a 3442:b 3434:= 3429:j 3425:x 3409:j 3405:x 3397:j 3393:a 3372:n 3361:n 3359:( 3349:n 3344:n 3335:n 3328:b 3316:n 3299:z 3279:y 3275:, 3272:x 3252:3 3249:= 3246:n 3231:i 3224:i 3220:a 3202:0 3199:a 3194:b 3174:= 3171:b 3168:+ 3163:n 3159:x 3153:n 3149:a 3145:+ 3139:+ 3134:2 3130:x 3124:2 3120:a 3116:+ 3111:1 3107:x 3101:1 3097:a 3065:n 3060:n 3036:= 3031:| 3025:1 3018:2 3014:y 3006:2 3002:x 2994:1 2987:1 2983:y 2975:1 2971:x 2963:1 2958:y 2953:x 2947:| 2922:0 2919:= 2916:) 2911:1 2907:y 2901:2 2897:x 2888:2 2884:y 2878:1 2874:x 2870:( 2867:+ 2864:y 2861:) 2856:1 2852:x 2843:2 2839:x 2835:( 2832:+ 2829:x 2826:) 2821:2 2817:y 2808:1 2804:y 2800:( 2774:= 2769:| 2761:1 2757:y 2748:2 2744:y 2736:1 2732:x 2723:2 2719:x 2709:1 2705:y 2698:y 2691:1 2687:x 2680:x 2674:| 2649:0 2646:= 2643:) 2638:1 2634:x 2627:x 2624:( 2621:) 2616:1 2612:y 2603:2 2599:y 2595:( 2589:) 2584:1 2580:y 2573:y 2570:( 2567:) 2562:1 2558:x 2549:2 2545:x 2541:( 2503:0 2500:= 2497:) 2492:1 2488:y 2482:2 2478:x 2469:2 2465:y 2459:1 2455:x 2451:( 2448:+ 2445:y 2442:) 2437:1 2433:x 2424:2 2420:x 2416:( 2413:+ 2410:x 2407:) 2402:2 2398:y 2389:1 2385:y 2381:( 2364:2 2361:x 2357:1 2354:x 2336:, 2333:0 2330:= 2327:) 2322:1 2318:x 2311:x 2308:( 2305:) 2300:1 2296:y 2287:2 2283:y 2279:( 2273:) 2268:1 2264:y 2257:y 2254:( 2251:) 2246:1 2242:x 2233:2 2229:x 2225:( 2195:. 2192:) 2187:1 2183:x 2176:x 2173:( 2165:1 2161:x 2152:2 2148:x 2140:1 2136:y 2127:2 2123:y 2116:= 2111:1 2107:y 2100:y 2077:. 2069:1 2065:x 2056:2 2052:x 2044:1 2040:y 2031:2 2027:y 2012:2 2009:x 2005:1 2002:x 1994:) 1992:2 1989:y 1985:2 1982:x 1980:( 1976:) 1974:1 1971:y 1967:1 1964:x 1962:( 1949:0 1946:y 1940:0 1937:x 1916:= 1909:0 1905:y 1901:y 1896:+ 1889:0 1885:x 1881:x 1865:0 1862:y 1856:0 1853:x 1827:) 1822:1 1818:x 1811:x 1808:( 1805:m 1802:= 1797:1 1793:y 1786:y 1760:. 1755:1 1751:x 1747:m 1739:1 1735:y 1731:+ 1728:x 1725:m 1722:= 1719:y 1693:, 1690:) 1685:1 1681:x 1674:x 1671:( 1668:m 1665:+ 1660:1 1656:y 1652:= 1649:y 1624:1 1620:y 1616:, 1611:1 1607:x 1596:m 1570:. 1565:b 1562:c 1554:= 1545:0 1541:y 1533:, 1528:a 1525:c 1517:= 1508:0 1504:x 1496:, 1491:b 1488:a 1480:= 1473:m 1443:, 1440:0 1437:= 1434:c 1431:+ 1428:y 1425:b 1422:+ 1419:x 1416:a 1386:. 1381:0 1377:x 1373:m 1367:x 1364:m 1361:= 1358:y 1332:, 1329:) 1324:0 1320:x 1313:x 1310:( 1307:m 1304:= 1301:y 1287:0 1284:x 1279:x 1262:. 1257:0 1253:y 1249:+ 1246:x 1243:m 1240:= 1237:y 1220:y 1216:y 1211:0 1208:y 1203:y 1199:m 1170:. 1165:b 1162:c 1154:= 1151:y 1139:a 1134:y 1128:a 1120:x 1106:, 1101:a 1098:c 1090:= 1087:x 1077:y 1067:b 1062:x 1052:b 1037:b 1033:a 1004:0 1001:= 998:c 995:+ 992:y 989:b 986:+ 983:x 980:a 967:) 965:y 961:x 959:( 951:b 947:y 934:a 930:x 905:c 892:c 861:. 856:b 853:c 837:y 820:b 817:a 774:. 769:b 766:c 758:x 753:b 750:a 742:= 739:y 726:y 722:x 718:y 701:0 698:= 695:c 692:+ 689:y 686:b 683:+ 680:x 677:a 662:b 643:b 639:a 632:0 628:b 624:a 610:, 607:0 604:= 601:c 598:+ 595:y 592:b 589:+ 586:x 583:a 573:y 569:x 545:a 542:b 534:= 531:x 508:0 502:a 482:, 479:0 476:= 473:b 470:+ 467:x 464:a 454:x 408:n 398:n 389:n 348:0 340:1 336:a 292:n 288:a 284:, 278:, 273:1 269:a 230:n 226:a 222:, 216:, 211:1 207:a 203:, 200:b 170:n 166:x 162:, 156:, 151:1 147:x 126:, 123:0 120:= 117:b 114:+ 109:n 105:x 99:n 95:a 91:+ 85:+ 80:1 76:x 70:1 66:a 34:. 20:)

Index

Linear equations
Linear differential equation

mathematics
equation
variables
unknowns
coefficients
real numbers
parameters
expressions
linear polynomial
field
solutions
Cartesian coordinates
Euclidean plane
line
hyperplane
Euclidean space
physics
engineering
non-linear systems
real numbers
complex
field
system of linear equations
Linear function (calculus)
function
graph
line

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