Solve Using the Square Root Property (x-20)^2=4

${(x - 20)}^{2} = 4$

Step 1

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

$x - 20 = \pm \sqrt{4}$

Step 2

Simplify $\pm \sqrt{4}$ .

Rewrite $4$ as $2^{2}$ .

$x - 20 = \pm \sqrt{2^{2}}$

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

$x - 20 = \pm 2$

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.

$x - 20 = 2$

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

Add $20$ to both sides of the equation.

$x = 2 + 20$

Add $2$ and $20$ .

$x = 22$

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

$x - 20 = - 2$

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

Add $20$ to both sides of the equation.

$x = - 2 + 20$

Add $- 2$ and $20$ .

$x = 18$

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

$x = 22, 18$