Types of Triangles

What is a triangle A plane figure, created by connecting three

points that are not in the same line.

Three – side polygon whose angles add up to 180°

Types of triagles and clasification Classified by Angles 1. Right triangle: when one of the int. angles is a

90° angle 2. Acute triangle: when one of the int. angles is

less than 90° 3. Obtuse triangle: when one of the int. Angles is

bigger than 90°

Classification by sides 1. Equilateral triangle: all 3 sides are the same

length, and the angles are the same measure (60°)

2. Isosceles triangle: 2 sides that have equal length, the base angles are the same angle

3. Scalene triangle: has no equal side lengths, or angle measures

Parts of a triangle

Triangle sum theorem All 3 angles of a triangle add up to 180°