Parallelogram, Diagonal, Circle, Vertex. Activate Flash plug-in or JavaScript and reload to view the Math Geometry Proposed Problems, online geometry classes, Geometry help, College, Online Learning.  Site created and maintained by Antonio Gutierrez.

Problem 474: Parallelogram, Diagonal, Circle, Vertex

The figure shows a parallelogram ABCD and a circle C1 passing through vertex C. Circle C1 intersects sides BC and CD at points E and F, respectively, and diagonal AC at point G. Prove that CA.CG = CB.CE + CD.CF.
 

Problem 474: Parallelogram, Circle, Diagonal