# How do you solve #(1/3)^x-9<18# using a graph?

##### 1 Answer

See below.

#### Explanation:

First Graph

This will give you the boundary between the included and excluded regions. Remember to use a dashed line, as this is a less than and not a less than or equal to inequality, so the line will not be an included region.

With the equation plotted, you will have to possible regions. These have been marked **A** and **B** on the graph. We need to test a pair of coordinates in each region to see which region satisfies the inequality.

**Region A**

coordinates

**TRUE**

**A** is an included region.

Now we have found our region, we do not really need to test **B**. Will will check this just for clarity.

**Region B**

coordinates

**FALSE**

**B** is an excluded region.

Shade region **A**