Solve Using the Square Root Property (x+9)^2=36

${(x + 9)}^{2} = 36$

Step 1

Take the specified root of both sides of the equation to eliminate the exponent on the left side.

$x + 9 = \pm \sqrt{36}$

Step 2

Simplify $\pm \sqrt{36}$ .

Rewrite $36$ as $6^{2}$ .

$x + 9 = \pm \sqrt{6^{2}}$

Pull terms out from under the radical, assuming positive real numbers.

$x + 9 = \pm 6$

Step 3

The complete solution is the result of both the positive and negative portions of the solution.

First, use the positive value of the $\pm$ to find the first solution.

$x + 9 = 6$

Move all terms not containing $x$ to the right side of the equation.

Subtract $9$ from both sides of the equation.

$x = 6 - 9$

Subtract $9$ from $6$ .

$x = - 3$

Next, use the negative value of the $\pm$ to find the second solution.

$x + 9 = - 6$

Move all terms not containing $x$ to the right side of the equation.

Subtract $9$ from both sides of the equation.

$x = - 6 - 9$

Subtract $9$ from $- 6$ .

$x = - 15$

The complete solution is the result of both the positive and negative portions of the solution.

$x = - 3, - 15$