Complete the following table. S. No Polygon Number of sides Number of diagonals (i) 3 (ii) Pentagon (iii) 7

As we know: In a polygon of n sides, the number of diagonals = n ( n - 3 ) 2 (i) Given: Number of sides in the polygon is 3 . As we know, a three-sided polygon is called a triangle. Using the above formula we get: Number of diagonals = 3 ( 3 - 3 ) 2 = 0 (ii) Given: Pentagon A pentagon is a polygon having 5 sides. Using the above formula we get: Number of diagonals = 5 ( 5 - 3 ) 2 = 5 diagonals. (iii) Given: Number of sides in the polygon is 7 . As we know, a seven-sided polygon is called a heptagon. Using the above formula we get: Number of diagonals = 7 ( 7 - 3 ) 2 = 14 diagonals. Hence, the complete table is as below: S. No Polygon Number of sides Number of diagonals (i) Triangle 3 0 (ii) Pentagon 5 5 (iii) Heptagon 7 14

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Number Magic a textbook of Mathematics 8>Chapter 3 - Polygons>EXERCISE

Monica Capoor Solutions for Chapter: Polygons, Exercise 2: EXERCISE

Author:Monica Capoor

Monica Capoor Mathematics Solutions for Exercise - Monica Capoor Solutions for Chapter: Polygons, Exercise 2: EXERCISE

Attempt the practice questions on Chapter 3: Polygons, Exercise 2: EXERCISE with hints and solutions to strengthen your understanding. Number Magic a textbook of Mathematics 8 solutions are prepared by Experienced Embibe Experts.