Question

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

Answer 1

See the entire solution process below:

Explanation:

First, add `color(red)(4)` to each side of the equation to isolate the `x^2` term while keeping the equation balanced:

`x^2 - 4 + color(red)(4) = 76 + color(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) = +-sqrt(80)`

`x = +-sqrt(80) = +-8.944` rounded to the nearest thousandth