first you need to get that equation in the y=mx+b form
2y = x+3 divide both sides by 2
y= (x+3)/2
you have it backwards, where you see y, you put -3/2 and where you see x you put 0.
(x, y) are how pairs are put together.
that is not right, at x=0 y = 1.5 not -3/2