Question 25539
y=2x-5  (1)
4x-y=7  (2)

From (1) we know that y = 2x-5
Put this back in (2)
4x-(2x-5) = 7

4x-2x+5 = 7
2x+5 = 7
Subtracting 5 on both sides
2x = 2
Dividing by 2 throughout
X = 1
which means y = 2(1)-5 = -3