Chord AC intersects chord BD at point P in circle Z. AP=4 cm BP=5 cm PC=8 cm What is PD?

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1 Answer
Mar 11, 2017

32/5=6.4 cm

Explanation:

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Intersecting Chord Theorem : when two chords intersect each other inside a circle, the products of their segments are equal.

This theorem states that AxxB is always equal to CxxD no matter where the chords are.

Back to our question,
Given AP=4, PC=8, and BP=5,
and by Intersecting Chord Theorem, we get,
APxxPC=BPxxPD

=> PD=(APxxPC)/(BP)=(4xx8)/5=32/5=6.4 cm