Question

How do you solve `x^ { 2} - 57= 87`?

Answer 1

See a solution process below:

Explanation:

First, add `color(red)(57)` to each side of the equation to isolate `x^2` while keeping the equation balanced:

`x^2 - 57 + color(red)(57) = 87 + color(red)(57)`

`x^2 - 0 = 144`

`x^2 = 144`

Now, take the square root of each side of the equation to solve for `x` while keeping the equation balanced. Remember, the square root of a number gives both a positive and negative result:

`sqrt(x^2) = +-sqrt(144)`

`x = +-12`