Point O is the center of the circle in the figure above. What is the value of \(x\) ?
Approach
If we draw a line segment from \(A\) to \(O\), we obtain an isosceles triangle since \(AO \text{ and } BO\) are both radii of the circle. Using our knowledge of isosceles triangles, \( m\angle OAB=15\degree \). We can then find \(m\angle AOB=150\degree\) by summing up the angles of the triangle to \(180 \degree\).
Similarly, \(m\angle AOC \) will also be equal to \(150\degree\). We can sum up the central angles: