LA5 marksYear: 2023MediumCBSE Class 10
trianglessimilar-trianglesAA-similarityproof
Question
D is a point on the side BC of a triangle ABC such that ∠ADC=∠BAC, prove that CA2=CB⋅CD.
Solution
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Triangle ABC with point D on side BC, angle ADC equals angle BAC
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In △CBA and △CDA: ∠C=∠C (common)
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∴△CBA∼△CAD (AA similarity)
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∴CACB=CDCA⇒CA2=CB⋅CD. Hence proved.
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