Examine the table. (Each figure is divided into triangles and the sum of the angles deduced from that)

What can you say about the angle sum of a convex polygon with number of sides?
(a) 7    (b) 8    (c) 10    (d) n

Solution:

From the table, it can be observed that the angle sum of a convex polygon of n sides is (n - 2) × 180

(a) When n = 7

Then angle sum of a polygon = (n - 2) × 180° = (7 - 2) × 180° = 5 × 180° = 900°

(b) When n = 8

Then angle sum of a polygon = (n - 2) × 180° = (8 - 2) × 180° = 6 × 180° = 1080°

(c) When n = 10

Then angle sum of a polygon = (n - 2) × 180° = (10 - 2) × 180° = 8 × 180° = 1440°

(d) When n = n

Then angle sum of a polygon = (n - 2) × 180°

☛ Check: NCERT Solutions for Class 8 Maths Chapter 3

Video Solution:

Examine the table. (Each figure is divided into triangles and the sum of the angles deduced from that.) What can you say about the angle sum of a convex polygon with number of sides? (a) 7 (b) 8 (c) 10 (d) n
 

NCERT Solutions Class 8 Maths Chapter 3 Exercise 3.1 Question 4

Summary:

We have been given the table. (Each figure is divided into triangles and the sum of the angles deduced from that.) The angle sum of the convex polygon with number of sides given are as follows: (a) n = 7, S = 900°, (b) n = 8, S = 1080°, (c) n = 10, S = 1440°, (d) n sides, S = (n - 2) × 180°

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