Finding Measures of Angles from Intersecting Lines

In the diagram below, two intersecting lines, line $l_1$ and line $l_2$, create four angles at the intersection point O. If angle AOB measures $$3x + 30^{ ext{°}}$$ and angle BOC measures $$5x - 30^{ ext{°}}$$, and it is given that angles AOB and BOC are supplementary, find the measure of angle AOB.