High School

Which of the numbers listed below are solutions to the equation [tex]$x^2 = -7$[/tex]? Check all that apply.

A. [tex]-\sqrt{7}[/tex]
B. 49
C. -3.5
D. [tex]\sqrt{7}[/tex]
E. -7
F. None of these

Answer :

To find which of the given numbers are solutions to the equation [tex]\( x^2 = -7 \)[/tex], we need to check which of these numbers, when squared, equals [tex]\(-7\)[/tex].

Here's the step-by-step process:

1. Squaring [tex]\(-\sqrt{7}\)[/tex]:
[tex]\[
(-\sqrt{7})^2 = (\sqrt{7})^2 = 7 \quad (\text{which is not } -7)
\][/tex]

2. Squaring 49:
[tex]\[
49^2 = 49 \times 49 = 2401 \quad (\text{which is not } -7)
\][/tex]

3. Squaring -3.5:
[tex]\[
(-3.5)^2 = 3.5^2 = 12.25 \quad (\text{which is not } -7)
\][/tex]

4. Squaring [tex]\(\sqrt{7}\)[/tex]:
[tex]\[
(\sqrt{7})^2 = 7 \quad (\text{which is not } -7)
\][/tex]

5. Squaring -7:
[tex]\[
(-7)^2 = 49 \quad (\text{which is not } -7)
\][/tex]

After evaluating each option, we see that:

- None of the numbers [tex]\(-\sqrt{7}, 49, -3.5, \sqrt{7},\)[/tex] and [tex]\(-7\)[/tex] satisfy the equation [tex]\( x^2 = -7 \)[/tex].

Therefore, the answer is:
F. None of these