Exercise 78 Page 155

To evaluate the given square root, we must first rewrite the number under the root. Then, we will calculate the square root of a squared number to evaluate the given expression.

Operation	Before Simplification	After Simplification
Write as a power	sqrt(9)	sqrt(3^2)
sqrt(a^2)=|a|	sqrt(3^2)	|3|
|3|=3	|3|	3

The expression equals 3.

Alternative Solution

Using a Calculator

We can also evaluate this expression using a calculator. To do so, type it as shown below.