BE and CF are two equal altitudes of a triangle ABC. Using RHS congruence rule. prove that the triangle ABC is isosceles
Given: BE and CF are two equal altitudes of a triangle ABC
To do: Prove triangle AC is an isosceles using RHS congruence.
Solution:
ABC is a triangle and BE and CF are two altitudes drawn from B and C on to opposite sides AC and AB respectively.
In the right triangles BCF and CBE
BC = BC [hypotenuse]
BE = CF [equal altitudes given]
angle BFC = angle BEC = 90 degrees
So the above triangles are congruent by RHS
So angle B = angle C [by CPCT]
So, the given triangle is an isosceles triangle.
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