During AMC testing, the AoPS Wiki is in read-only mode and no edits can be made.

Two Tangent Theorem

Revision as of 02:06, 11 July 2025 by Knoxrocks (talk | contribs)

The two tangent theorem states that given a circle, if P is any point lying outside the circle, and if A and B are points such that PA and PB are tangent to the circle, then PA = PB. <geogebra>4f007f927909b27106388aa6339add09df6868c6</geogebra>

Proofs

Proof 1

Since $OBP$ and $OAP$ are both right triangles with two equal sides, the third sides are both equal.

Proof 2

From a simple application of the Power of a Point Theorem(or Power Point Theorem), the result follows.

See Also

This article is a stub. Help us out by expanding it.