Answer
$x=-7, 1$
Work Step by Step
To complete the square, add a term that is the square of half the coefficient of $x$ to both sides of the equation. Then use the square root property to simplify both sides, and then isolate $x$.
$x^2+6x=7$
$(\frac{6}{2})^2=(3)^2$
$x^2+6x+(3)^2=7+(3)^2$
$x^2+6x+9=7+9$
$x^2+6x+9=16$
$(x+3)^2=16$
$x+3=±4$
$x=-3±4$
$x=-7, 1$
