Answer :
[tex]5x+3y=-12 \ \ \ |\times (- 7) \\
8x+7y=-6 \ \ \ | \times 3\\ \\
-35x-21y=84 \\
\underline{24x+21y=-18 \ } \\
-35x+24x=84-18 \\
-11x=66 \ \ \ |\div (-11) \\
x=-6 \\ \\
5x+3y=-12 \\
5 \times (-6)+3y=-12 \\
-30+3y=-12 \ \ \ |+30 \\
3y=18 \ \ \ |\div 3 \\
y=6 \\ \\
\boxed{(x,y)=(-6,6)}
[/tex]
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)
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)