Answer
$y=\pm\dfrac{7}{2}$
Work Step by Step
Using the properties of equality, the given equation, $
4y^2=49
,$ is equivalent to
\begin{array}{l}\require{cancel}
y^2=\dfrac{49}{4}
.\end{array}
Taking the square root of both sides, then the solutions of the given equation are
\begin{array}{l}\require{cancel}
y=\pm\sqrt{\dfrac{49}{4}}
\\\\
y=\pm\sqrt{\left(\dfrac{7}{2}\right)^2}
\\\\
y=\pm\dfrac{7}{2}
.\end{array}