Geometry

We can rewrite the angles as $\angle A = 60^\circ$, $\angle B = 60^\circ+x$, and $\angle C = 60^\circ+2x$. Now, we can use the Triangle Sum Theorem to solve for $x$. We can make the equation $60+60+x+60+2x=180$ Solving for $x$ gets $x=0$, so therefore all of the angles are $60^\circ$ so $\angle C = 60^\circ$.