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Question
Contruct a ΔABC with BC = 6.5 cm, AB = 5.5 cm, AC = 5 cm. Construct the incircle of the triangle. Measure and record the radius of the incricle.
Solution
Steps of construction:
- Draw BC = 6.5 cm.
- With B as centre, draw an arc of radius 5.5 cm.
- With C as centre, draw an arc of radius 5 cm.
Let this arc meets the previous arc at A. - Join AB and AC to get ΔABC.
- Draw the bisectors of ∠ABC and ∠ACB.
Let these bisectors meet each other at O. - Draw ON ⊥ BC.
- With O as centre and radius ON, draw a incircle that touches all the side of ΔABC.
- By measurement, radius ON = 1.5 cm.
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