Steps of construction :
(1) Draw a line AB = 5 cm.
(2) Mark a point C on AB such that AC = 3 cm.
(3) Draw a perpendicular bisector of AC.
(4) Mark a point O on perpendicular bisector from A of length 2.5 cm.

(5) Taking O as centre and OA as radius draw a circle, which is the required circle.
(6) Join O and B.
(7) Draw a circle with OB as diameter which cuts the given circle at points P and Q.
(8) Join PB and QB, which are the required tangents. QB = PB = 3 cm
Here, length of tangents is 3 cm.