Mathematics
If chords AB and CD of a circle intersect each other at a point P inside the circle, prove that : PA × PB = PC × PD.
Circles
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Answer
In △PAC and △PDB
∠APC = ∠DPB (Vertically opposite angles are equal)
∠CAP = ∠BDP (Angles in same segment are equal)
∴ △PAC ~ △PDB
We know that,
When two triangles are similar, the ratio of the lengths of their corresponding sides are proportional.
∴
⇒ PA × PB = PC × PD.
Hence, proved that PA × PB = PC × PD.
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