Slope intercept form is y = mx + b
2x - 4y + 7 = 0
The y must be on one side by itself.
The easiest way to do this is just move the y and then reorder.
Add 4y to both sides.
2x + 7 = 4y
Divide both sides by 4
(2/4)x +(7/4) = y
Now reorder so that the y is on the left and reduce the fraction.
y = (1/2)x + (7/4)