Question

if two supplement angles are in the ratio of 4:5 then find the angles

Answer 1

4u + 5u = 9u

9u = 180 degrees

1u = 180 degrees / 9 = 20 degrees

4u = 20 degrees x 4 = 80 degrees

5u = 20 degrees x 5 = 100 degrees

The angles are 80 degrees and 100 degrees respectively.

Answer 2

Let the angles be x

As they are in ratio of 4:5 ,so we can write it in the form of 4x ,5x

We know supplementary angle =180°

so,According to the question

4x+5x =180°

9x =180°

x =180°÷9

x =20°

so , 1 st angle = 4x =4×20° =80°

2 nd angle = 5x = 5×20° =100°

◆PROOF◆

4x + 5x =180°

4×20° +5×20° =180°

80°+ 100°=180°

180° =180°

[VERIFIED]