Find a solution to the system of equations by elimination

12x-9y=-15

-4x-8y=-28

12x - 9y = - 15

Let's divide both sides by 3.

4x - 3y = - 5

The other equation is

-4x - 8y = - 28

Adding equations,

-11y = - 33

y = 3

4x = 3y - 5 = 3 (3) - 5 = 4

x = 1

Answer: x=1, y=3

Check:

12 (1) - 9 (3) = -15, good

-4 (1) - 8 (3) = - 28, good