To solve for
d, the first step is to combine all like terms and try to get
d isolated on one side of the equals sign. The only like terms that we can see are
d and 3
d — but that's it. So, we can subtract
d from both sides to end up with 5
c = 2
d - 1. Because we want to isolate
d, now we must add 1 to both sides to get 5
c + 1 = 2
d. But this isn't our answer, because there is still a coefficient attached to
d. Therefore we must divide both sides by 2 to receive a final answer of

.