Introduction to Triangles

Introduction to Triangles 1 & 2

Open Ended

What do you know about triangles?

Classification of Triangles by ANGLES

• Right Triangle - One  $90\degree$  angle

• Acute Triangle - Three Acute angles

• Obtuse Triangle - One Obtuse angle

• Equiangular - all  $60\degree$  angles

Classification of Triangles by SIDES

• Isosceles Triangle - Two Congruent Sides

• Scalene Triangle - No Congruent Sides

• Equilateral Triangle - Three Congruent Sides

Triangle Sum Theorem

The sum of the interior angles in a triangle is  $180\degree$  

How do we use all this information about triangles to solve problems?