Question

ABCD is a parallelogram.​

Answer 1

Answer:

80

Step-by-step explanation:

sum of angle A and B is 180

5x+4x = 180

9x = 180

x =20 so angle B = 80

Answer 2

Answer:∠B=80

Step-by-step explanation:

Here, ∠A+∠B=180 (Adjacent angles in a parallelogram are supplementary)

Therefore, 5x+4x=180

∴9x=180

∴x=180/9

∴x=20

Here we know that ∠B=4x

∴∠B=4×20=80