Respuesta :
In the second step he should have had s+2 again rather than 2+4. Other than that, it's fine. A corrected version would look like this:
[tex] A: \frac{A}{6}=(s+2)^2 \implies\\
B: \pm\sqrt{\frac{A}{6}}=s+2 \implies\\
C: \pm\frac{\sqrt{A}}{\sqrt{6}}=s+2\implies \\
D:\pm\frac{\sqrt{6A}}{6}=s+2 \implies\\
E:-2\pm\frac{\sqrt{6A}}{6}=s [/tex]
The plus or minus is irrelevant, you cannot have a negative area or volume, but I don't think that's the problem.
Answer:
Nathan made a mistake in step B.
Step-by-step explanation:
Given formula:
[tex]A=6(s+2)^2[/tex]
The correct steps to find the surface area of a cube whose side length is s + 2 units are
Step A : Divide both sides by 6.
[tex]\frac{A}{6}=(s+2)^2[/tex]
Step B : Taking square root both sides.
[tex]\pm \sqrt{\frac{A}{6}}=s+2[/tex]
Step C : Distribute square root.
[tex]\pm \frac{\sqrt{A}}{\sqrt{6}}=s+2[/tex]
Step D : Rationalize denominator.
[tex]\pm \frac{\sqrt{6A}}{6}=s+2[/tex]
Step E : Subtract 2 from both sides.
[tex]-2\pm \frac{\sqrt{6A}}{6}=s[/tex]
Therefore, Nathan made a mistake in step B.