Page 149 - New Medley 5 Semester 2

1. Draw a ray OA using a ruler and a pencil.
O A
2. Place a protractor on the ray OA so that the centre point falls on O
and the baseline coincides the ray OA.

3. Using the pencil tip, mark a point next to the

marking of 40° angle. Name the point, say B.
Note that the right side of the baseline coincides

the ray OA, so it is read on inner scale.

4. Remove the protractor and join the point O to
point B.

B B

40°
O A 40°
O A

Thus, ∠AOB is of 40°.
Constructing an Angle of 125 °

To construct an angle of measure 125°, follow these steps:

1. Draw a ray OX using a ruler and a pencil. O X
2. Place a protractor on the ray OX so that the

centre point falls on O and the right side of the
baseline coincides the ray OX. Mark a point,
say Y, with the marking of 125° on inner scale.

3. Remove the protractor and draw the ray OY
using ruler and a pencil.

Y
Y
125°
O X 125°
O X
Thus, the angle formed is ∠XOY = 125°.

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