Question

2. The angles A, B, C, D of a quadrilateral ABCD are in the ratio 1:3:7:9.
(a) Find the measure of each angle.
(b) Give the special name of quadrilateral ABCD.
(5)​

Answer 1

Answer:

∠A:∠B:∠C:∠D=1:2:3:4

So, let ∠A=x,∠B=2x,∠C=3x,∠D=4x

Therefore, by angle sum property of quadrilateral,

x+2x+3x+4x=360

10x=360

x=36°

Hence,

∠A=36°

∠B=72 °

∠C=108 °

∠D=144 °