1 answer
(click or scroll down)
To solve the equation \(x^2 = 81\) by inspection, we can take the square root of both sides. The equation implies that:
\[
x = \pm \sqrt{81}
\]
Calculating the square root, we find:
\[
\sqrt{81} = 9
\]
Thus, the solutions are:
\[
x = 9 \quad \text{and} \quad x = -9
\]
Therefore, the complete solution set is:
\[
\{-9, 9\}
\]
The correct response is:
\(\{-9, 9\}\)