Solve for u u^2=9

$u^{2} = 9$

Step 1

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

$u = \pm \sqrt{9}$

Step 2

Simplify $\pm \sqrt{9}$ .

Rewrite $9$ as $3^{2}$ .

$u = \pm \sqrt{3^{2}}$

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

$u = \pm 3$

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.

$u = 3$

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

$u = - 3$

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

$u = 3, - 3$