# Table of Contents

Definition of an isosceles triangle and its elements

The types of isosceles triangles

Criteria for an isosceles triangle

The perimeter and the semiperimeter of an isosceles triangle

The area of an isosceles triangle. Formulas

The lengths of the sides of an isosceles triangle

The angles of an isosceles triangle and their properties

The angle bisector of an isosceles triangle and its properties

The height of an isosceles triangle and its properties

The median of an isosceles triangle and its properties

Similarity of isosceles triangle

Symmetry in an isosceles triangle

The inscribed circle’s center of an isosceles triangle

The inscribed circle’s radius of an isosceles triangle. Formulas