4.b.2 - 2014 Q5
The shape ABCDEA, as shown in Figure 2, consists of a right-angled triangle EAB and a
triangle DBC joined to a sector BDE of a circle with radius 5 cm and centre B.
The points A, B and C lie on a straight line with BC = 7.5 cm.
Angle EAB = π/2 radians, angle EBD = 1.4 radians and CD = 6.1 cm.
(a) Find, in cm2, the area of the sector BDE. (2)
(b) Find the size of the angle DBC, giving your answer in radians to 3 decimal places. (2)
(c) Find, in cm2, the area of the shape ABCDEA, giving your answer to 3 significant figures. (5)
The points A, B and C lie on a straight line with BC = 7.5 cm.
Angle EAB = π/2 radians, angle EBD = 1.4 radians and CD = 6.1 cm.
(a) Find, in cm2, the area of the sector BDE. (2)
(b) Find the size of the angle DBC, giving your answer in radians to 3 decimal places. (2)
(c) Find, in cm2, the area of the shape ABCDEA, giving your answer to 3 significant figures. (5)