Question

5x+3y=-12 and 8x+7y=-6
solve the following systems of equations

Answer 1

5x + 3y = -12 ⇒ 40x + 24y = -96
8x + 7y = -6 ⇒ 40x + 35y = -30
-11y = -66
-11 -11
y = 6
5x + 3(6) = -12
5x + 18 = -12
-18 -18
5x = -30
5 5
x = -6
(x, y) = (-6,6)

Answer 2

`5x+3y=-12 \ \ \ |* (- 7) \\ 8x+7y=-6 \ \ \ | * 3\\ \\ -35x-21y=84 \\ \underline{24x+21y=-18 \ } \\ -35x+24x=84-18 \\ -11x=66 \ \ \ |/ (-11) \\ x=-6 \\ \\ 5x+3y=-12 \\ 5 * (-6)+3y=-12 \\ -30+3y=-12 \ \ \ |+30 \\ 3y=18 \ \ \ |/ 3 \\ y=6 \\ \\ \boxed{(x,y)=(-6,6)}`