Page 1 - Lesson Notes-Tangents Ch-10 (Circles)
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SAI International School
Class X
Mathematics – Lesson Notes
Chapter-10: Circles
Sub Topics –No. of Tangents from a point to a circle, Theorem 10.2
No. of Tangents from a point to a circle-
i. There is no tangent to a circle passing through a point lying inside the circle.
ii. There is one and only one tangent to a circle passing through a point lying on the circle.
iii. There are exactly two tangents to a circle through a point lying outside the circle.
Theorem 10.2- The lengths of tangents drawn from an external point to a circle are equal.
Given: A circle with centre O; PA and PB are two tangents to the circle drawn from an
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