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Working rule to construct a tangent to a circle (Using Alternate Segment Theorem):
Given the radius of a circle, let us learn how to construct a tangent to the circle using its alternate segment theorem.
Example:
Draw a circle of radius 4 cm. Then, at a point L on it, draw a tangent to the circle using the alternate segment.
Rough Sketch:
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Construction:
Step 1: With O as the centre, draw a circle of radius 4 cm.
Step 2: Take a point L on the circle. Through L, draw any chord LM.
Step 3: Take two points M and N distinct from L on the circle, so that L, M and N are in anti-clockwise direction. Join LN and NM.
Step 4: Through L draw a tangent TT' such that \angle TLM = \angle MNL.
Step 5: TT' is the required tangent.
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