Answer
$\{-11,11\}$
Work Step by Step
Taking the square root of both sides (Square Root Property), the given equation, $
t^2=121
,$ is equivalent to
\begin{align*}
t&=\pm\sqrt{121}
.\end{align*}
Using concepts of simplifying radicals, the equation above is equivalent to
\begin{align*}
t&=\pm\sqrt{(11)^2}
\\
t&=\pm11
.\end{align*}
Hence, the solution set of $
t^2=121
$ is $
\{-11,11\}
$.
