To solve the equation \(x^2 + 9 = 45\), we start by isolating \(x^2\):
\[ x^2 + 9 = 45 \] Subtracting 9 from both sides, we get:
\[ x^2 = 45 - 9 \] \[ x^2 = 36 \]
Next, we take the square root of both sides:
\[ x = \pm \sqrt{36} \] \[ x = \pm 6 \]
This means the solutions are \(6\) and \(-6\).
Now let's compare this with what each person said:
- Trey said the solution is \({6}\).
- Amelia said the solution is \({-6, 6}\).
- Cho said the solution is \({-6}\).
The correct solution set is \({-6, 6}\), which matches Amelia's answer.
Therefore, the correct response is:
Amelia