Isosceles Triangle Theorem Proof

In the triangle two sides is equal length is called as the isosceles triangle. The pronunciation of the word isosceles is the “eye-sos-ell-easy”, It is some triangles that have two sides the similar length. The isosceles triangle include the unequal angle is also known as base triangle. The isosceles the third angle is the right angle is known as the right isosceles triangle.


The Isosceles Triangle Theorem Statement:



In the triangle the sides are the same the length. The isosceles triangle, the two sides are equal to the triangle. The isosceles of the triangle is the important one of the triangle. The isosceles triangle is the also called as the pons asinorum. The isosceles triangle theorem proof is the easy way. In the following we see how to prove the isosceles triangle theorem.


The Euclid’s theorem is the fundamental angle of the isosceles triangles is the equal. The Isosceles Triangles proof is one kinds of the triangle. In these types of the Isosceles Triangles proof has containing 2 sides are the same. The stand angles are the angles is opposites of the two equal angles.

Theorem proof:





Angle BAC=angle CAB (the angle is congruent to itself)

In the triangle ∠BAC is the triangle ∠CAB (Side-Angle-Side)

Therefore, angle B=angle C


First, assume 1 and 2 are true. Since AD is a median, BD CD. Since AD is an altitude, AD and BC are perpendicular. Thus, ∠ADB and ∠ADC are right angles and therefore congruent. Since we have

AD AD by the reflexive property of

ADB`~=` ADC 

BD `~=` CD

these two diagram represent the isosceles triangle theorm proof

Way of the Isosceles Triangles Theorems Proof:

Isosceles Base Angles Theorem:

          If the two sides of the triangle are equal, then the angle reverse those sides is the same.

this is the sample example of the isosceles base angles theorem


The Converse of the Base Angles Theorem:

          In the isosceles the converse of the base angles theorem, two angles states of a triangle are similar, and then sides differing those angles are matching.

the converse of the base angles therem of the isosceles