Which of the following triplets cannot be the angles of a triangle?
a. 67°, 51°, 62°
b. 70°, 83°, 27°
c. 90°, 70°, 20°
d. 40°, 132°, 18°

Solution:

We have to find the triplets that cannot be the angles of a triangle.

By angle sum property of a triangle,

We know that the sum of all the three interior angles of the triangle is equal to 180 degrees.

(i) considering 67°, 51°, 62°

Sum of angles = 67°+ 51°+ 62°

= 67° + 113°

= 180°

Therefore, 67°, 51°, 62° can be the angles of a triangle.

(ii) considering 70°, 83°, 27°

Sum of angles = 70°+ 83°+ 27°

= 97° + 83°

= 180°

Therefore, 70°, 83°, 27° can be the angles of a triangle.

(iii) considering 90°, 70°, 20°

Sum of angles = 90°+ 70°+ 20°

= 90° + 90°

= 180°

Therefore, 90°, 70°, 20° can be the angles of a triangle.

(iv) considering 40°, 132°, 18°

Sum of angles = 40°+ 132°+ 18°

= 58° + 132°

= 190°

Therefore, 40°, 132°, 18° cannot be the angles of a triangle.

✦ Try This: In a triangle ABC, ∠C = 60°, and ∠A = 90°. Find the measure of ∠B

☛ Also Check: NCERT Solutions for Class 7 Maths Chapter 6

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NCERT Exemplar Class 7 Maths Chapter 6 Problem 30

Which of the following triplets cannot be the angles of a triangle? (a) 67°, 51°, 62°, (b) 70°, 83°, 27°, (c) 90°, 70°, 20°, (d) 40°, 132°, 18°

Summary:

Out of the following triplets, 40°, 132°, 18° cannot be the angles of a triangle

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