Question

1. Solve the linear system using substitution.

4x-y=5
4x+4y=-4

Answer 1

substitute y=4x-5 into 4x+4y=-4 to get

4x+4(4x-5) = -4
4x+16x-20 = -4
20x = 16
x = 4/5
so, y = -9/5