Q1 of 805 Page 11

Draw a circle of radius 6 cm. From a point 10 cm away from its center, construct the pair of tangents to the circle and measure their lengths.

Step 1: Take a point O as center, draw a circle of 6 cm radius.



Step 2: Take another point A away 10 cm from Center. Join A and O.



Step 3: Now, bisect OA. We get P as a mid point of OA.


Step 4: Now, construct a circle of OA radius and P as a center.



Step 5: Now, circle intersect the previous circle at Q and R.



Step 6: Join AQ and AR.


Justification:


It can be justified by prove that


AQ and AR are tangents.


Join OQ and OR


∠AQO=90°


AQ ⊥OQ


Since OQ=radius, AQ has to be a tangent Similarly AR is a tangent.



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