Solve each system of equations using substitution. Show all work.
1) y = 2x - 5
4x - y = 7
2) 2x - 3y = 12
x = 4y + 1
3) y = 5 - x
x - 4y = 10
1) y = 2x - 5
4x - y = 7
2) 2x - 3y = 12
x = 4y + 1
3) y = 5 - x
x - 4y = 10