# Question #855d3

##### 1 Answer

#### Explanation:

We need to choose and define a variable.

Let the width of the border be

Now we can define the length and width of the mural, remembering that the border is on both sides.

Length of mural =

width of mural =

The area of the wall is

The area of the mural is 75% of this:

Now we have enough information to write an equation and solve it.

Using the formula:

Estimating which value we should use gives the following:

Obviously we cannot subtract 13 twice from either the length or the width, so the second answer is the one we need.