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Question
Using ruler and compasses only, draw an equilateral triangle of side 5 cm. Draw its inscribed circle. Measure the radius of the circle.
Solution
Steps of construction:
- Draw a line segment BC = 5 cm.
- With centers B and C, draw two arcs of 5 cm radius each which intersect each other at A.
- Join AB and AC.
- Draw angle bisectors of ∠B and ∠C intersecting each other at O.
- From O, draw OL ⊥ BC.
- Now with centre O and radius OL, draw a circle which will touch the sides of ΔABC.
On measuring, OL = 1.4 cm.
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