Question

Answer the 18th one step by step

Answer 1

Answer:

Step-by-step explanation:

Given in parallelogram ABCD, where  AO and BO are bisectors of angle A and angle B respectively.

We know that sum of adjacent angles in a parallelogram is 180°

 angle A + angle B = 180

2 x + 2 y = 180

  x + y = 90                  → (1)

In ΔAOB,

               x + y + angle AOB = 180

               90 + angle AOB = 180            →from 1

              angle AOB = 90

               hence, found

     

In ΔAOB,  (Sum of angles in a triangle is 180°)

 [From (1)]