Missing Angles in a Triangle

Front

What is the sum of the angles in a triangle?

Back

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

Front

If one angle in a triangle is 90 degrees, what type of triangle is it?

Back

It is a right triangle.

Front

What is an acute angle?

Back

An acute angle is an angle that measures less than 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.

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

Which of the following sets of angles can form a triangle? 120°, 50°, 20°; 100°, 200°, 60°; 30°, 50°, 80°; 40°, 50°, 90°?

Back

Only 40°, 50°, 90° can form a triangle.

Front

What is the definition of a triangle?

Back

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

Front

What is the relationship between the angles in a triangle?

Back

The angles in a triangle are related such that their sum is always 180 degrees.

Front

If two angles in a triangle are 60 degrees and 60 degrees, what is the measure of the third angle?

Back

The third angle measures 60 degrees, making it an equilateral triangle.

Front

What is the definition of a scalene triangle?

Back

A scalene triangle is a triangle with all sides of different lengths and all angles of different measures.