Question 175
In the figure below, $ABC$ is an isosceles triangle with $BA = BC$. The point $D$ is in its interior so that $\angle ABD = 13^{\circ}$, $\angle ADB = 150^{\circ}$ and $\angle ACD = 30^{\circ}$. Moreover, $ADE$ is an equilateral triangle. Determine the value of the angle $\angle DBC$.
