Question

If consecutive angles of a parallelogram are in the ratio of 4:5,then their measures are​

Answer 1

Answer:

∠A = 80°

∠B = 100°

∠C = 80°

∠D = 100°

Step-by-step explanation:

We know that ,

the opposite angles in a parallelogram are equal .

Lets take the measure of the angles as ∠A , ∠B , ∠C , ∠D

∠A = ∠C

∠B = ∠D

∠A : ∠B = 4 : 5                                 [ given ]

And , ∠A + ∠B = 180°

4x + 5x = 180

9x = 180

x = 180 / 90

  = 20

∠A = 4x

      = 80°

∠A = ∠C

∴ ∠C = 80°

∠B = 5x

     = 100°

∠B = ∠D

∴ ∠D = 100°

Hope it helped and please mark as brainliest :)

Answer 2

Let one angle be equal to 4x and other 5x

We know that

sum of consecutive( or adjacent) angles of parallelogram = 180°

So, 4x + 5x = 180°

9x = 180°

x = 180/9

x = 20°

One Angle = 4* 20 = 80°

Other angle = 5* 20 = 100°