Answer:
x = r + (1/2)d
Step-by-step explanation:
If you're solving for x, you have to undo the multiplication between the x and the 4 by doing the opposite operation. Division is opposite of multiplication, so if you divide the 4x by 4, you have to divide everything on the other side of the equals sign by 4 since this is an equation. 4r/4 = r, and 2d/4 = 1/2 d