Question

15. The measure of one of the exterior angles of a triangle is 70° and the interior opposite
angles are in the ratio 2: 5. The measure of the largest angle of the triangle is
b) 500
d) 110°
a) 700
c) 20°

Answer 1

Let the angle 1 and 2 be 2x and 5x respectively.

Angle 1= 2x

Angle 2= 5x

Angle 3= 180-70= 110°

Angle 1+2+3 = 180°

2x+5x+110= 180°

7x= 180-110

7x= 70°

x= 70/7

x= 10°

Angle 1= 2x= 2*10= 20°

Angle 2 = 5x= 5*10= 50°

Angle 3= 110°

Therefore 110° is the largest angle.