Classifying, Triangle Angle Sum, Isosceles

Front

What is a triangle?

Back

A triangle is a polygon with three edges and three vertices. It is one of the basic shapes in geometry.

Front

What are the types of triangles based on side lengths?

Back

1. Equilateral Triangle: All sides are equal. 2. Isosceles Triangle: Two sides are equal. 3. Scalene Triangle: All sides are different.

Front

What are the types of triangles based on angles?

Back

1. Acute Triangle: All angles are less than 90°. 2. Right Triangle: One angle is exactly 90°. 3. Obtuse Triangle: One angle is greater than 90°.

Front

What is the Triangle Angle Sum Theorem?

Back

The sum of the interior angles of a triangle is always 180°.

Front

If a triangle has one angle of 90°, what type of triangle is it?

Back

It is a Right Triangle.

Front

What is an Isosceles Triangle?

Back

An Isosceles Triangle has at least two sides that are equal in length and the angles opposite those sides are equal.

Front

What is an Equilateral Triangle?

Back

An Equilateral Triangle has all three sides of equal length and all three angles equal to 60°.

Front

If a triangle has one angle greater than 90°, what type of triangle is it?

Back

It is an Obtuse Triangle.

Front

What is a Scalene Triangle?

Back

A Scalene Triangle has all sides of different lengths and all angles of different measures.

Front

How do you find the measure of an unknown angle in a triangle?

Back

Subtract the sum of the known angles from 180°.