Some of the steps for completing the square to solve [tex]$x^2+5x=2$[/tex] are shown.

[tex]\[
\begin{aligned}
x^2 + 5x & = 2 \\
x^2 + 5x + \left(\frac{5}{2}\right)^2 & = 2 + \left(\frac{5}{2}\right)^2 \\
\left(x + \frac{5}{2}\right)^2 & = \frac{33}{4}
\end{aligned}
\][/tex]

Which are solutions of [tex]$x^2 + 5x = 2$[/tex]? Check all that apply.

A. [tex]\frac{5}{2} + \frac{\sqrt{33}}{4}[/tex]

B. [tex]\frac{5}{2} + \frac{\sqrt{33}}{2}[/tex]

C. [tex]\frac{5}{2} - \frac{\sqrt{33}}{2}[/tex]

D. [tex]-\frac{5}{2} + \frac{\sqrt{33}}{2}[/tex]

E. [tex]-\frac{5}{2} + \frac{\sqrt{33}}{2}[/tex]



Answer :

Let's solve the given equation [tex]\( x^2 + 5x = 2 \)[/tex] by completing the square:

1. Given:
[tex]\[ x^2 + 5x = 2 \][/tex]

2. We complete the square on the left-hand side:
[tex]\[ x^2 + 5x + \left(\frac{5}{2}\right)^2 = 2 + \left(\frac{5}{2}\right)^2 \][/tex]

3. Simplify:
[tex]\[ x^2 + 5x + \left(\frac{5}{2}\right)^2 = 2 + \left(\frac{5}{2}\right)^2 \][/tex]
[tex]\[ x^2 + 5x + \frac{25}{4} = 2 + \frac{25}{4} \][/tex]
[tex]\[ x^2 + 5x + \frac{25}{4} = \frac{8}{4} + \frac{25}{4} \][/tex]
[tex]\[ x^2 + 5x + \frac{25}{4} = \frac{33}{4} \][/tex]

4. Write the left-hand side as a perfect square:
[tex]\[ \left(x + \frac{5}{2}\right)^2 = \frac{33}{4} \][/tex]

5. Take the square root of both sides:
[tex]\[ x + \frac{5}{2} = \pm \sqrt{\frac{33}{4}} \][/tex]
[tex]\[ x + \frac{5}{2} = \pm \frac{\sqrt{33}}{2} \][/tex]

6. Solve for [tex]\( x \)[/tex]:
[tex]\[ x = -\frac{5}{2} \pm \frac{\sqrt{33}}{2} \][/tex]

7. This gives us two solutions:
[tex]\[ x = -\frac{5}{2} + \frac{\sqrt{33}}{2} \][/tex]
and
[tex]\[ x = -\frac{5}{2} - \frac{\sqrt{33}}{2} \][/tex]

Now we need to identify which of the given options match the solutions we found.

Given options:
1. [tex]\(\frac{5}{2} + \frac{\sqrt{33}}{4}\)[/tex]
2. [tex]\(\frac{5}{2} + \frac{\sqrt{33}}{2}\)[/tex]
3. [tex]\(\frac{5}{2} - \frac{\sqrt{33}}{2}\)[/tex]
4. [tex]\(-\frac{5}{2} + \frac{\sqrt{33}}{2}\)[/tex]
5. [tex]\(-\frac{5}{2} - \frac{\sqrt{33}}{2}\)[/tex]

Compare with our solutions:
- [tex]\(\frac{5}{2} + \frac{\sqrt{33}}{2}\)[/tex] does not match our solutions.
- [tex]\(\frac{5}{2} - \frac{\sqrt{33}}{2}\)[/tex] does not match our solutions.
- [tex]\(-\frac{5}{2} + \frac{\sqrt{33}}{2}\)[/tex] matches [tex]\(-\frac{5}{2} + \frac{\sqrt{33}}{2}\)[/tex]
- [tex]\(-\frac{5}{2} - \frac{\sqrt{33}}{2}\)[/tex] matches [tex]\(-\frac{5}{2} - \frac{\sqrt{33}}{2}\)[/tex]
- [tex]\(\frac{5}{2} + \frac{\sqrt{33}}{4}\)[/tex] does not match our solutions.

Hence, the correct solutions are:
- [tex]\(-\frac{5}{2} + \frac{\sqrt{33}}{2}\)[/tex]
- [tex]\(-\frac{5}{2} - \frac{\sqrt{33}}{2}\)[/tex]