# What is the rule for subtraction with exponents: ie r^5 - r^4?

Jul 17, 2017

#### Answer:

There is no rule to write it as one term. See explanation.

#### Explanation:

If you want to write this expression as a single power ${r}^{a}$ then there is no such rule for subtraction. Only power, multiplication or division can be written in such way.

Only thing you can do is to factorize the expression.