To solve the equation \( x^2 = \frac{36}{169} \), we can take the square root of both sides:
\[ x = \pm \sqrt{\frac{36}{169}} \]
Next, we can simplify the square root:
\[ x = \pm \frac{\sqrt{36}}{\sqrt{169}} = \pm \frac{6}{13} \]
Therefore, the solutions are:
\[ x = \frac{6}{13} \quad \text{and} \quad x = -\frac{6}{13} \]
Thus, the solution set is:
\[ \left{-\frac{6}{13}, \frac{6}{13}\right} \]
So the correct response is:
\({ -\frac{6}{13}, \frac{6}{13} }\)