# How do you solve #9=7z-13z-21#?

##### 2 Answers

Apr 15, 2018

#### Explanation:

You combine

Add

Divide both sides by

Apr 15, 2018

#### Explanation:

When solving equations, we can combine like terms as shown below:

So to solve this problem, we need to isolate the variable "

We do this by combining all terms with the variable

Then we treat it as a regular algebra problem by isolating the variable

Note: Combining like terms can only be done with variables of the same degree, or in other words, variables raised to the same exponent. Example below: