5.1-5.4 Triangle Relationships

Front

What is an acute triangle?

Back

A triangle where all three angles are less than 90 degrees.

Front

What is an isosceles triangle?

Back

A triangle with at least two sides of equal length.

Front

What is an obtuse triangle?

Back

A triangle that has one angle greater than 90 degrees.

Front

What is a scalene triangle?

Back

A triangle with all sides of different lengths.

Front

What is the vertex angle in a triangle?

Back

The angle opposite the base, typically the angle formed by the two equal sides in an isosceles triangle.

Front

What does the Triangle Sum Theorem state?

Back

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

Front

What is the Exterior Angle Theorem?

Back

The measure of an exterior angle of a triangle is equal to the sum of the measures of its remote interior angles.

Front

If one angle of a triangle is 60 degrees, what is the maximum possible measure of the other two angles?

Back

The maximum possible measure of the other two angles is 120 degrees combined, since the total must equal 180 degrees.

Front

What is the relationship between the angles in a right triangle?

Back

One angle is exactly 90 degrees, and the sum of the other two angles is 90 degrees.

Front

How do you classify a triangle with one 90-degree angle?

Back

It is classified as a right triangle.