What is/are the solution(s) to x2 = 169/225 ?

$x^2 = \dfrac{169}{225}$

$x = \sqrt{\dfrac{169}{225}} = \dfrac{\sqrt{169}}{\sqrt{225}}$

$x = \dfrac{\pm 13}{\pm 15}$

 

basically your solutions are just $\dfrac{13}{15}$ and $-\dfrac{13}{15}.$ nice!