Question

Find the measure of the third angle of triangles whose two angles are given below
(i) 38°,102° (ii) 116°,30° (iii) 40°,80°
In a right angled triangle one acute angle is 30°. Find the other acute angle. ​

Answer 1

(I)38°,102°

Let the other angle be x

sum of angle of a ∆le is 180°

38°+102°+x=180°

x=180°-140°

=40°

(ii) 116°,30°

Let the other angle be x

sum of angle of a ∆le is 180°

116°+30°+x=180°

x=180°-146°

=34°

(III)40°,80°

Let the other angle be x

sum of angle of a ∆le is 180°

40°+80°+x=180°

x=180°-120°

=60°