Q25 of 46 Page 1

Construct tangents to a circle of radius 4 cm from a point on the concentric circle of radius 7 cm.

Steps of construction:


1. Draw a circle of radius 4cm with centre O.



2. Draw concentric circle of radius 7cm, with centre O.



3. Mark point P on the larger circle.



4. Make perpendicular bisector of PO and let M be the midpoint of PO.



5. Taking M as centre and MO as radius, draw a circle.



6. The circle intersect at points Q and R.



7. Join P to Q and P to R



∴ PQ and PR are the required tangents.


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