Question

choose a method (in photo) to apply to problem and solve for all variables in simplest radical form

Answer 1

The triangle in the picture is a right triangle and we can relate the sides length with the Pyhtagorean theorem:

$\begin{gathered} x^2+13^2=16^2 \\ x^2+169=256 \\ x^2=256-169 \\ x^2=87 \\ x=\sqrt[]{87} \end{gathered}$

Answer: x = √87