Question

prove the theorem 7.2 i e. angles opposite to equal dide of sn isosceles triangle are equal.





today my exam please help me​

Answer 1

Answer:

Given: an isosceles triangle ABC with AB = AC

to prove: Angle A = Angle C

construction: draw the angle bisector of angle AD of angle A.

consider triangle ABC and triangle ACD

AB = AC(given)

AD = AD (common)

angle BAD = angle CAD(AD is the angle bisector)

therefore my SAS congruence,

∆ABD are congruent to ∆ACD

therefore by CPCT Angle B = angle C