Question

An angle is 20° less than 1/4
of its supplement. Then complement of the angle is
(A) 15°
(C) 60°
(B) 70°
(D) 55°​

Answer 1

Answer:

Let angle be x

Supplementary angles: The angles which have their sum as equal to 180°

Supplement of x = 180 - x

Thus: x = 1/4(180 - x) - 20

=> 4x = 180 - x - 80

=> 5x = 100

=> x = 20°

Complementary angles: The angles which have their sum as equal to 90°

Complement of 20° = 90 - 20 = 70°

Answer: (b) 70°

Thank You!

__________________

Answer 2

Answer: Opt.B) 70°

Step by step explanation:

Given:

An angle is 20° less than 1/4 of its supplement.

To find: complement of the angle.

Solution:

Let the angle be x.

Supplement of x = 180° - x

.°. 1/4(180 - x) - 20 = x

180 - x - 80 = 4x

5x = 100

x = 20°

Now,

Complement of angle = 90° - x

= 90° - 20°

= 70°

Thus, The complement of the angle is 70° (Opt.B)

[ Supplementary angles are the two angles whose sum is 180° while complementary angles are two angles whose sum is 90°.]