## Introductory Algebra for College Students (7th Edition)

$x=\{−6,2\}$
The left side of the given equation, $x^2+4x+4=16$, is a perfect square trinomial whose factored form is $(x+2)^2=16$. Taking the square root of both sides (the Square Root Property), the solutions to the given equation are $x+2=\pm\sqrt {16}$ $x+2=\pm\sqrt {(4)2}$ $x+2=\pm4$ $x=−2+4$ or $x=-2-4$ $x=2$ or $x=-6$ Hence, $x=\{−6,2\}$.