4x-3y=-40

9x+5y=4

x=?

y=?

How do I do this?

Multiply the first equation by 5

20x - 15y = - 200

multiply the second equation by 3

27x + 15y = 12

add the 2 new equations

20x-15y + 27x + 15y = - 200 + 12

47x = - 188 (devide each side by 47)

x = - 4

substitute x with - 4 in any equation you like (I'll choose the second)

9 * (-4) + 5y = 4

-36+5y=4 (add 36 to each side)

5y = 40

y = 8