Triangles- Angles, Sides, and Their Relationships

Front

What is a triangle?

Back

A triangle is a polygon with three edges and three vertices.

Front

What are the types of triangles based on angles?

Back

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

Front

What are the types of triangles based on sides?

Back

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

Front

What is the sum of the angles in a triangle?

Back

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

Front

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

Back

Subtract the sum of the known angles from 180 degrees.

Front

What is the Triangle Inequality Theorem?

Back

The sum of the lengths of any two sides of a triangle must be greater than the length of the third side.

Front

Can a triangle be formed with sides of lengths 2, 3, and 6?

Back

No, because 2 + 3 is not greater than 6.

Front

What is an acute angle?

Back

An acute angle is an angle that measures less than 90 degrees.

Front

What is a right angle?

Back

A right angle is an angle that measures exactly 90 degrees.

Front

What is an obtuse angle?

Back

An obtuse angle is an angle that measures more than 90 degrees but less than 180 degrees.