Isosceles and equilateral triangle properties

What you'll learn

1. State and apply the base angles theorem: if two sides of a triangle are equal, the angles opposite those sides are equal
2. Use the converse: if two angles of a triangle are equal, the sides opposite those angles are equal
3. Recognize that an equilateral triangle has three 60-degree angles and three equal sides
4. Solve for unknown angles and sides in isosceles and equilateral triangles, including algebraic expressions

Prerequisites

• Triangle angle sum and exterior angle theorem