Slope intercept form is y=mx+b
so to rewrite it in that, all you do is solve for y
1/2x - 3y = 16
subtract 1/2x from both sides.
-3y = 16 - 1/2x
divide both sides by -3.
y = (16 - 1/2x)/-3
y = -16/3 + 1/6x
rearrange the terms so its in y=mx+b
y = 1/6x - 16/3