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Question
Using ruler and compasses only, draw tangents to a circle of radius 3 cm from a point 5 cm from the centre. What is the length of each of them ?
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Solution

Steps of oonstruction:
(i) Draw a cirde of radius 3 cm with centre O.
(ii) Join the centre O to the given point P which is 5 cm away from O.
(iii) Draw a perpendicular bisector of OP. Let M be the mid-point of OP.
(iv) With Mas centre and radius OM, draw a circle cutting the first circle at A and B.
(v) Join PA and PB.
(vi) PA and PB are the required tangents.
(vii) On measuring, PA and PB = 4 cm
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