Q7 of 805 Page 11

Draw a circle with the help of a bangle. Take a point outside the circle. Construct the pair of tangents from this point to the circle.

Step1: Draw a circle from a bangle.


Step2: Take a point A outside the circle and two chords BC and DE.


Step3: Bisect chords. They intersect at point O.


Step4: join OA and bisect it. We get midpoint of OA is P. Taking P as a center draw a circle of OP radius which intersect circle at W and X.


Join AW and AX. These are tangent.



Justification:


We have to be proved that O is center of circle.


Join OW and OX.


∠AWO=90° (angle is on semicircle)


OW is perpendicular to AW.


Since, OW is radius of circle, AW has to be tangent. Similarly AX is tangent.


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