Q15 of 20 Page 11

Draw a pair of tangents inclined to each other at an angle of 60° to a circle of radius 3 cm.

Given angle between tangents is 60°.


i.e. ∠ APB = 60°


Since angle subtended is double the angle between tangents.


∠AOB = 2× 60° = 120°


So, we need to draw ∠AOB = 120°


∴ we draw a radius, then second radius at 120° from first.


Also,


Tangent is perpendicular to radius.


So,


OA ⊥ AP and OB⊥ AP.


Thus, to make tangents, we draw perpendiculars from A and C.


Steps of construction:


1. Draw a circle of radius 3 cm, with center O.



2. Draw OA and OB, such that A and B lie on the circumference of circle and ∠OAB = 120°



3. Draw AX ⊥ OA and BY ⊥ OB



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