If the altitudes from two vertices of a triangle to the opposite sides are equal, then the triangle is

It is given in the question that,

In ∆ABC, BL is parallel to AC


Also, CM is parallel AB such that BL = CM


We have to prove that: AB = AC


Now, in ∆ABL and ∆ACM we have:


BL = CM (Given)


BAL = CAM (Common)


ALB = AMC (Each angle equal to 90o)


By AAS congruence criterion


∆ABL ACM


AB = AC (By Congruent parts of congruent triangles)


As opposite sides of the triangle are equal, so it is an isosceles triangle


Hence, option (B) is correct

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