Respuesta :
Answer:
The Isosceles Triangle Theorem States that if a triangle contains 2 congruent sides, then the angles opposite those sides are congruent. This theorem can be proved using the Law of Sines: The Law of Sines states that: asinA=bsinB=csinC If a=c, making △ABC an isosceles triangle, then asinA=asinC!
The law of sins says: a/SinA = b/SinB = c/sinC
For this to be an isosceles triangle then side a must equal side c
so then a/sinA = c/sinC
Then you can divide both sides by a and raise to the power of -1 and you would get angle A = angle C which makes this isosceles.