Interior and Exterior Angles of a Triangle

Front

What is the sum of the interior angles of a triangle?

Back

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

Front

What is an exterior angle of a triangle?

Back

An exterior angle of a triangle is formed by one side of the triangle and the extension of an adjacent side.

Front

How do you calculate an exterior angle of a triangle?

Back

An exterior angle can be calculated by adding the two opposite interior angles.

Front

What is the relationship between an exterior angle and its adjacent interior angle?

Back

The exterior angle is equal to the sum of the two opposite interior angles.

Front

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

Back

It is a right triangle.

Front

What is the formula to find the measure of an unknown angle in a triangle?

Back

To find an unknown angle, subtract the sum of the known angles from 180 degrees.

Front

What is the definition of an acute triangle?

Back

An acute triangle is a triangle where all three interior angles are less than 90 degrees.

Front

What is the definition of an obtuse triangle?

Back

An obtuse triangle is a triangle that has one interior angle greater than 90 degrees.

Front

How can you determine if a triangle is equilateral?

Back

A triangle is equilateral if all three sides are of equal length and all three interior angles are equal, each measuring 60 degrees.

Front

What is the relationship between the angles in a triangle and the sides opposite those angles?

Back

In a triangle, the larger the angle, the longer the side opposite that angle.