Question 1

1. AOD = 92

   DOB = 88

   DCB = 44

2. Angle ADB is 90 because the angle at the centre is twice the angle at the circumference. Since the angle at a straight line at AOB is 180, ADB must be 90.

3. 12^2 + 6^2 = x2

   144 + 36 = x^2

   180 = x^2

   x = 6√5

4. A = pi r^2

   A = pi (3√5)^2

   = 45 pi

Question 2

1. 21/30

2. 21/30 x 20/29 = 14/29

3. P ( A ∩ B) = P(A) x P(B)

   21/175 = 85/175 X 30/175

   0.12 ≠ 0.083

Question 3

tan23 = P/x

x = P/tan23

P = x tan23

tan14 = P/(x+5)

x+5 = P/tan14

x = (P/tan14) -5

P = (x+5) tan14

x tan23 = (x+5) tan14