SOLUTION: Prove: If the base and a leg of one isosceles triangle are congruent to the base and a leg of another isosceles triangle, then their vertex angles are congruent.

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Question 1138612: Prove: If the base and a leg of one isosceles triangle are congruent to the base and a leg of another isosceles triangle,
then their vertex angles are congruent.
Answer by ikleyn(52777)   (Show Source): You can put this solution on YOUR website!
.
If the base and a leg of one isosceles triangle are congruent to the base and a leg of another isosceles triangle,

then these triangles have three pairs congruent sides.


    Do you understand it ?


It means, due to SSS triangles congruence test, that the triangles are congruent.


Hence, their corresponding angles are congruent.


The vertex angles are corresponding - so, they are congruent.

The proof is completed.

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