Solve for w w^2-4=0

$w^{2} - 4 = 0$

Add $4$ to both sides of the equation.

$w^{2} = 4$

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

$w = \pm \sqrt{4}$

Simplify $\pm \sqrt{4}$ .

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

$w = \pm \sqrt{2^{2}}$

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

$w = \pm 2$

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.

$w = 2$

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

$w = - 2$

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

$w = 2, - 2$