Question

Two angles in a triangle are in ratio 4:5.If the sum of these angles is equal to third angle. Find the third angle.​

Answer 1

Answer:

let the common factor for ratio be x.

angle one=4x

angle 2 = 5x

3 angle = 4x+5x=9x

sum angle of a =180 degree

ATQ,

4x+5x+9x = 180

18x =180

x=18

1. 4x=4*18=72
2. 5x=5*18=90
3. 9x=9*18=162

Answer 2

Let the measure of two angles be 4x and 5x and the third one is ( 4x + 5x ).

We know that ;

Sum of angles of triangle = 180°

⇒ 4x + 5x + 4x + 5x = 180

⇒ 18x = 180

⇒ x = 180/18

⇒ x = 10

Therefore, the angles are ;

4x = 4 * 10 = 40°

5x = 5 * 10 = 50°

9x = 9 * 10 = 90°