Solve a = d+c/b for d.

To solve for d, you need to get d by itself on one side of the equals sign!

Since d + c/b is currently on one side of the equals sign, all you have to do is move the c/b to the other side of the equation (to the other side of the equals sign with the a).

To do this, you should subtract c/b from both sides of the equation.

You then get:

a - c/b = d

D is now by itself - you solved for d and your work is done.