The next step is to identify which, if any, terms can be combined. Remember, only like terms — constant terms or terms with the same variable — can be combined.
- 2d - 4e + 15d - 40e
In this case, we have two d-terms and two e-terms. Both the d-terms and the e-terms can be combined, so to simplify the expression we will rearrange it according to Commutative Property of Addition and then combine like terms.
