In the figure $\angle{AOB} = 90^{\circ} $. Then the value of $x$ is <br> <p>

Question

$\begin{array}{1 1} (a)\; 13.6^{\circ} \\ (b)\; 15.2^{\circ} \\ (c)\; 13^{\circ} \\ (d)\; 15^{\circ} \end{array}$