(a)[2]
Find the angle $BAD$ in radians.
(b)[4]
Find the perimeter of the shaded area.
Mathematics 9709 · AS & A Level · Circular measure
Circular measure — practice question
The figure presents triangle $ABC$, where angle $ABC = 90^\circ$ and $AB = 4\text{ cm}$. Sector $ABD$ is part of a circle centred at $A$. Its area is $10\text{ cm}^2$.