Problem: Circle O has diameters AB and CD perpendicular to each other. AM is any chord intersecting CD at P. Then APâ‹…AM is equal to:
Answer Choices:
A. AOâ‹…OB
B. AOâ‹…AB
C. CPâ‹…CD
D. CPâ‹…PD
E. COâ‹…OP
Solution:
ABM is a right triangle. By similar triangles, AP/AB=AO/AM. ∴AP⋅AM=AO⋅AB.