Answer
$x=-1 \text{ and } x=3$
Work Step by Step
Subtract $4$ from each side:
$$x^2-2x-3=0$$
Factor the trinomial:
$$(x-3)(x+1)=0$$
Use the Zero-Product Property by equating each factor to zero, then solve each equation to obtain:
\begin{align*}
x-3&=0 &\text{or}& &x+1=0\\
x&=3 &\text{or}& &x=-1
\end{align*}
Thus, the solutions are $x=-1 \text{ and } x=3$.