Replace x with 1/2 then solve for y:
5(1/2) - 2y = 4
2 1/2 -2y = 4
Subtract 2 1/2 from each side:
-2y = 1 1/2
Divide both sides by -2:
y = 1 1/2 / -2
y = -3/4
5.2m questions
6.8m answers