(a)[1]
Find the simplest expression, in terms of $x$, for angle $AOB$.
(b)[1]
Find the simplest expression, in terms of $x$, for angle $ACB$.
(c)[2]
Find the simplest expression, in terms of $x$, for angle $DAB$.
Mathematics 0580 · IGCSE · Circle theorems II
Circle theorems II — practice question
In the circle shown, $A$, $B$, $C$ and $D$ all lie on the circumference, with centre $O$. Angle $ACD = x^{\circ}$ and angle $OAB = 2x^{\circ}$. The sketch is marked NOT TO SCALE.