D is a point on the side BC of a triangleABC such that ADC = BAC. Show that CA2 = CB.CD

In ΔADC and ΔBAC,


ADC = BAC (Given)


ACD = BCA (Common angle)


ΔADC ΔBAC (By AA similarity)


We know that corresponding sides of similar triangles are in proportion


Hence,



CA2 = CB * CD


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