solve the linear system using substitution

Question

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

Also by using elimination.

Answer 1

substitution: since you have y = 4x-5,
4x + 4(4x-5) = -4
20x = 16
x = 4/5
y = -9/5

using elimination, subtract one equation from the other to get

5y = -9
y = -9/5
now solve for x to get x=4/5