How do you solve the following system?: $21 x + 14 y = 3, - 14 x - 59 y = - 12$ $21x +14y = 3 , -14x - 59y = -12$

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Answer 1 · 2018-06-15T18:15:28

$x = - \frac{351}{623}$ $x=-351/623$ and $y = \frac{30}{89}$ $y=30/89$

$2 \cdot (21 x + 14 y) + 3 \cdot (- 14 x - 59 y) = 2 \cdot 3 + 3 \cdot (- 12)$ $2*(21x+14y)+3*(-14x-59y)=2*3+3*(-12)$

$42 x + 28 y - 42 x - 117 y = 6 - 36$ $42x+28y-42x-117y=6-36$

$- 89 y = - 30$ $-89y=-30$ , so $y = \frac{- 30}{- 89} = \frac{30}{89}$ $y=(-30)/(-89)=30/89$

Hence,

$- 14 x - 59 \cdot \frac{30}{89} = - 12$ $-14x-59*30/89=-12$

$- 14 x - \frac{1770}{89} = - 12$ $-14x-1770/89=-12$

$- 1246 x - 1770 = - 1068$ $-1246x-1770=-1068$

$- 1246 x = 702$ $-1246x=702$

$x = \frac{702}{- 1246} = - \frac{351}{623}$ $x=702/(-1246)=-351/623$

How do you solve the following system?: 21x+14y=3,−14x−59y=−1221x +14y = 3 , -14x - 59y = -12