SOLUTION: Given circle T; and a point P outside of T;, 2 lines l1 and l2 are drawn such that both pass through P. l1 intersects T; at A and B, and l2 intersects T; at C and D, with C between
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-> SOLUTION: Given circle T; and a point P outside of T;, 2 lines l1 and l2 are drawn such that both pass through P. l1 intersects T; at A and B, and l2 intersects T; at C and D, with C between
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Question 697522: Given circle T; and a point P outside of T;, 2 lines l1 and l2 are drawn such that both pass through P. l1 intersects T; at A and B, and l2 intersects T; at C and D, with C between D and P. If PA=44,PB=294 and PC=56, what is PD? Answer by Edwin McCravy(20060) (Show Source):
PA=44,PB=294 and PC=56, what is PD?
Draw BC and AD
Angles B and D are inscribed angles intersepting
the same arc AC so they are equal.
Angle P is in both triangles. Therefore triangles
PAD and PCB are similar, therefore
=
Cross-multiplying:
PA×PB = PC×PD
44×294 = 56×PD
12936 = 56×PD
= PD
231 = PD
So PD = 231
Edwin