# How do you solve x^2-4=76?

Feb 13, 2017

See the entire solution process below:

#### Explanation:

First, add $\textcolor{red}{4}$ to each side of the equation to isolate the ${x}^{2}$ term while keeping the equation balanced:

${x}^{2} - 4 + \textcolor{red}{4} = 76 + \textcolor{red}{4}$

${x}^{2} - 0 = 80$

${x}^{2} = 80$

Now, take the square root of each side of the equation to solve for $x$ while keeping the equation balanced. Remember, when taking the square root of a number there will be a negative and positive solution:

$\sqrt{{x}^{2}} = \pm \sqrt{80}$

$x = \pm \sqrt{80} = \pm 8.944$ rounded to the nearest thousandth