Question:
Diagonals of a quadrilateral ABCD bisect each other. If ∠A= 35°, determine ∠B.
Solution:
Since, diagonals of a quadrilateral bisect each other, so it is a parallelogram.
Therefore, the sum of interior angles between two parallel lines is 180° i.e.,
∠A+∠B = 180°
=> ∠B = 180° – ∠A = 180°- 35°
[∴ ∠A = 35°, given]
=> ∠B = 145°