Solve for x x^2=12^2+5^2

$x^{2} = 12^{2} + 5^{2}$

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

$x = \pm \sqrt{12^{2} + 5^{2}}$

Simplify $\pm \sqrt{12^{2} + 5^{2}}$ .

Raise $12$ to the power of $2$ .

$x = \pm \sqrt{144 + 5^{2}}$

Raise $5$ to the power of $2$ .

$x = \pm \sqrt{144 + 25}$

Add $144$ and $25$ .

$x = \pm \sqrt{169}$

Rewrite $169$ as $13^{2}$ .

$x = \pm \sqrt{13^{2}}$

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

$x = \pm 13$

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.

$x = 13$

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

$x = - 13$

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

$x = 13, - 13$