Triangle Theorems

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 acute triangle?

Back

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

Front

What is a right triangle?

Back

A right triangle is a triangle that has one angle equal to 90 degrees.

Front

What is an obtuse triangle?

Back

An obtuse triangle is a triangle where one angle is greater than 90 degrees.

Front

What is the Triangle Sum Theorem?

Back

The Triangle Sum Theorem states that the sum of the angles in a triangle is 180 degrees.

Front

If one angle of a triangle is 60 degrees and another is 90 degrees, what is the measure of the third angle?

Back

The third angle measures 30 degrees.

Front

What is the Exterior Angle Theorem?

Back

The Exterior Angle Theorem states that the measure of an exterior angle is equal to the sum of the measures of the two opposite interior angles.

Front

In a triangle, if two angles are equal, what type of triangle is it?

Back

It is an isosceles triangle.

Front

What is the Pythagorean Theorem?

Back

In a right triangle, the square of the length of the hypotenuse is equal to the sum of the squares of the lengths of the other two sides (a² + b² = c²).

Front

If the angles of a triangle are in the ratio 2:3:4, what are the measures of the angles?

Back

The angles measure 40 degrees, 60 degrees, and 80 degrees.