Page 160 - Start Up Mathematics_5

Step 1: Draw a ray YZ of some length. Y Z

X
Step 2: Keep the centre of the protractor at
vertex Y so that the baseline coincides
with YZ.

Step 3: Now measure the inner scale till you
reach 60° mark. Mark it with a dot as
point X. Y
Z

6

5 1cm2 X
Step 4: Remove the protractor. Join point X 3
with Y. 4 4

Hence, ∠XYZ = 60°. 5
3 7 6

Y Z
8
9

EXERCISE 12.1

1. Measure the following angles using a protractor.

C P
A
(a) (b) (c)

B
O C Q
D R

A M
(d) (e) Z (f)

O B X Y N L

2. Draw the following angles using a protractor.
(a) 25° (b) 30° (c) 45° (d) 65°

(e) 80° (f) 100° (g) 110° (h) 150°
(i) 145° (j) 160° (k) 90° (l) 55°

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