Question

Construct a direct common tangent to two congruent circles of radii 3.5 cm, each and whose centres are 7 cm apart.

Answer 1

Radius of each circle = 3.5 cm

Distance between their centers = 7 cm

The steps below need to be followed to draw the direct common tangents to the given circles.

1. Draw OO′ = 7 cm

2. Draw two circles of radius 3.5 cm each, with O and O′ as their centers respectively.

3. Draw perpendiculars at O and O′ that intersect the circle with centre O at A and B, and the circle with centre O′ at M and N.

4. Join AM and BN.

Thus, AM and BN are the two direct common tangents.