Question

Using ruler and compasses only, draw an equilateral triangle of side 4.5 cm and draw its circumscribed circle. Measure the radius of the circle.

Answer 1

Steps of Construction:

i) Draw a line segment BC = 4.5 cm

ii) With centres B and C, draw two arcs of 4.5 cm radius each which intersect each other at A.

iii) Join AB and AC.

iv) Draw angle bisectors of ∠B and ∠C intersecting each other at O.

v) From O, draw OL ⊥ BC.

vi) Now with centre O and radius OL, draw a circle which will touch the sides of ΔABC