Answer
$y=\{-5,-1\}$
Work Step by Step
Using the completing the square method, the solutions of the given quadratic equation, $
y^2+6y=-5
,$ is
\begin{array}{l}\require{cancel}
y^2+6y+\left( \dfrac{6}{2} \right)^2=-5+\left( \dfrac{6}{2} \right)^2
\\\\
y^2+6y+9=-5+9
\\\\
(y+3)^2=4
\\\\
y+3=\pm\sqrt{4}
\\\\
y+3=\pm2
\\\\
y=-3\pm2
\\\\
y=\{-5,-1\}
.\end{array}
