Question 1 - Page 235 - Rotational Symmetry - Chapter 9 Class 6 - Symmetry (Ganita Prakash)

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Question 1 - Page 235 Can you draw a figure with radial arms that has a) exactly 5 angles of symmetry, b) 6 angles of symmetry? Also find the angles of symmetry in each case. Hint: Use 5 radial arms for the first case. What should the angle between two adjacent radial arms be?To make a figure with 3 angles of symmetry, We made a fan with 3 arms Similarly, To make 5 angles of symmetry, we make fan with 5 arms To make 6 angles of symmetry, we make fan with 5 arms 5 angles of symmetry The angle of symmetry would be Angle of symmetry = (360° )/5 = 72° Thus, the figure would be same at angles 72° 72° × 2 = 144° 72° × 3 = 216° 72° × 4 = 288° 72° × 5 = 360° So, we write Angles of symmetry = 72°, 144°, 216°, 288°,360° 6 angles of symmetry The angle of symmetry would be Angle of symmetry = (360° )/6 = 60° Thus, the figure would be same at angles 60° 60° × 2 = 120° 60° × 3 = 180° 60° × 4 = 240° 60° × 5 = 300° 60° × 6 = 360° So, we write Angles of symmetry = 60°, 120°, 180°, 240°, 300° , 360°