Q13 of 65 Page 138

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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