In a quadrilateral ABCD, the bisector of ∠C and ∠D meet at point E. If ∠CED = 57o and ∠A = 47o, then the measure of ∠B is:
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 67o
In Quadrilateral ABCD,
∠A+∠B+∠C+∠D = 360
now, triangle CED
∠CDE +∠ECD +∠CED = 180
(∠C+∠D)/2 + ∠CED =180
(∠C+∠D)/2 + 57 = 180
(∠C+∠D)/2 =123
∠C+∠D = 246
then, ∠A+∠B + 246 = 360
47+∠B+246 = 360
∠B = 360-293 = 67