Question

quadrilateral ABCD AC=AD and AB a bisector angle A show that the triangle ABC is congruent to triangle ABD.

Answer 1

GIVEN: ABCD is a quadrilateral

AC=AD

AB is the bisector of angle A (i.e) angle BAD = angle BAC

TO PROVE: Triangle ABC is congruent to triangle ABD

PROOF:AC=AD (GIVEN)

AB=BA (COMMON FOR BOTH TRIANGLES)

Angle BAD= Angle BAC (GIVEN)

So we can say that triangle ABC is congruent to triangle ABC