Given: r1 = 17 cm, r2 = 2.8 cm and the distance between these centers C12 = 56 cm.
To Construct : indirect (transversal) common tangent.
Steps of Construction:
(1) Draw a line segment of the length of 6 cm the distance between two centers C1C2
(2) Taking C1 as center and radius 1.7 cm draw a circle.
(3) Taking C2 as center and radius 2.8 cm draw another circle.
(4) Draw the perpendicular bisector of C1C2 which intersects it at M.
(5) Taking M as center and radius MC1 = MC2 draw another circle.
(6) Taking the radius equal to the sum of two radii center C1 the centre of smaller circle draw a circle.
i.e., radius 1.7 + 2.8 = 4.5 cm and center C1 which intersects the circle with diameter C1C2 at A and B.
(7) Join AC2 and AC1 which intersect the circle radius 1.7 cm at P.
(8) Join P to Q.
Hence, PQ is the required indirect common tangent