Question

Solve: 3x-3y=3 y=-5x-17

Answer 1

Substitute y = -5x - 17 into the first equation:
-3x - 3y = 3
-3x - 3*(-5x - 17) = 3

-3x + 15x + 51 = 3
-3x + 15x = 3 - 51
12x = -48
x =-48/12 = -4 

y = -5x - 17 = -5*(-4) - 17 = 20 - 17 = 3 

so the solution is x = -4, y = 3