3. Exemplar - Find the unknown angle

The tangent at a point \(C\) of a circle and a diameter \(AB\) when extended intersect at \(P\). If \(\angle PCA = 100^\circ\), evaluate \(\angle CBA\). [Hint: Join \(C\) with centre \(O\)]

 

 

\(\angle CBA = \) \(^\circ\)