Answer
The solution set is $\left\{-1, 1\right\}$.
Work Step by Step
Add $-1$ to both sides to obtain:
$x^2-1=0$
RECALL:
A difference of two square can be factored using the formula:
$a^2-b^2=(a-b)(a+b)$
Factor the difference of two squares to obtain:
$(x-1)(x+1)=0$
Equate each factor to 0, and then solve each equation to obtain:
$x-1=0 \text{ or } x+1 = 0
\\x=1 \text{ or } x =-1$
The solution set is $\left\{-1, 1\right\}$.
