Power of a Point Theorem/Introductory Problem 4
(ARML) Chords and of a given circle are perpendicular to each other and intersect at a right angle at . Given that and , find .
is a right triangle with hypotenuse 5 and leg 4. Thus, by the Pythagorean Theorem, (or by just knowing your Pythagorean Triples). Applying the Power of a Point Theorem gives , or . Solving gives .
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