Question

is it important that in isosceles that opposite side should be equal or the any two sides?​

Answer 1

Answer:

You may observe that in each such triangle, the angles opposite to the equal sides are equal. This is a very important result and is indeed true for any isosceles triangle. It can be proved as shown below. Theorem : Angles opposite to equal sides of an isosceles triangle are equal.

Answer 2

Properties of Triangles (Learn) : Maths : Class 9 : Amrita Vidyalayam ... You may observe that in each such triangle, the angles opposite to the equal sides are equal. This is a very important result and is indeed true for any isosceles triangle. It can be proved as shown below. Theorem : Angles opposite to equal sides of an isosceles triangle are equal.