(a)[2]
Calculate the area enclosed by triangle $AOB$.
(b)[2]
Calculate the area enclosed by sector $AOD$.
(c)[4]
Calculate what percentage of the circle's area is shaded.
Mathematics 4024 · O Level · Circles, arcs and sectors
Circles, arcs and sectors — practice question
The circle is centred at $O$, and AC and BD are diameters. Here, $AC = 12\,\text{cm}$ and $\angle A\hat{O}B = 130^\circ$.