Construct a tangent to a circle of radius 4 cm from a point on the concentric circle of radius 6 cm and measure its length. Also, verify the measurement by actual calculation.

Steps of Construction:


1. With O as center, draw a circle of radius of 4cm and another circle of radius 6cm.



2. Mark any point A on the bigger circle.


3. Join OA. Draw perpendicular bisector of OA.


4. The perpendicular bisector XY of OA intersects OA at B.



5. With B as center and radius of length OB (or BA), draw a circle.


6. This circle intersects the smaller circle(of radius 4cm) at P and Q.



7. Join AP and AQ.


8. Then AP and AQ are the required tangents.



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