Question

Draw the incircle of equilateral triangle of side 5 cm. Measure the radius of the circle. [3 Marks]

Answer 1

Steps of Construction:

i) Draw a line segment BC = 5 cm

ii) With B and C as centers, draw two arcs of radius 5 cm each which intersect each other at A [1 Mark]

iii) Join AB and AC.

iv) Draw angle bisectors of $\angle B$ and $\angle C$ intersecting each other at O. [1 Mark]

v) From O draw ON perpendicular to BC.

vi) Now with centre O and radius ON, draw a circle which will touch all the three sides of the triangle. Measure ON . ON = 1.4 cm. [1 Mark]