ABCD is a cyclic quadrilateral in which ∠A = x°, ∠B = 5y°, ∠C = 2x° and ∠D = y°. What is the value of (3x - y) ?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 150
The sum of a pair of opposite angles is 180°
∠A + ∠C = 180°
x + 2x = 180°
3x = 180°
x = 60°
∠B + ∠D = 180°
5y + y = 180°
6y = 180°
y = 30°
(3x - y) = (60 × 3 - 30) = 150