Page 58 - Concepts of Reasoning-8

CHAPTER

Worksheet-12.1 polygon and quadrilaterals 12

Polygons

1. With the help of the figures shown below, state whether the following statements are true
or false :

2 cm

140° 150° 35° 30° 120° 120° 4 cm 108° 4 cm
2 cm 2 cm
65° 145° 108° 108°
70° 120° 120°
310°
4 cm 4 cm
135° 2 cm 2 cm
145° 150° 65° 120° 120° 108° 108°
2 cm 4 cm
a. The polygon in the figure 1 is a convex polygon. ___________

b. The polygon in the figure 2 is a concave polygon. ___________

c. Figure 3 is an irregular polygon. ___________

d. Figure 4 is a regular polygon. ___________

2. Fill the table for regular polygons :

Polygon Sum of interior Sum of Measure of Measure of
angles exterior angles each interior angle each exterior angle

a. Triangle
b. Hexagon

c. Octagon

d. Decagon

3. Solve the following word problems :

a. The four angles of a quadrilateral are 10x, 12x and 30x respectively. Find the angles.

___________________________________________________________________________

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b. The four angles of a quadrilateral are 20x – 30, 25x – 25, 5x + 15 and 4x + 22 respectively. Find the
angles.

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58 Reasoning - 8