Triangle Theorems

Front

What is the Triangle Sum Theorem?

Back

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

Front

If one angle of a triangle is 90°, what can you say about the other two angles?

Back

The other two angles must sum to 90°.

Front

What is the longest side of a right triangle called?

Back

The longest side of a right triangle is called the hypotenuse.

Front

What does the Triangle Inequality Theorem state?

Back

The Triangle Inequality Theorem states that the sum of the lengths of any two sides of a triangle must be greater than the length of the third side.

Front

If the longest side of a triangle is 10, what must be true about the other two sides?

Back

The sum of the lengths of the other two sides must be greater than 10.

Front

What is an acute triangle?

Back

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

Front

What is an obtuse triangle?

Back

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

Front

What is a scalene triangle?

Back

A scalene triangle is a triangle where all three sides are of different lengths.

Front

What is an isosceles triangle?

Back

An isosceles triangle is a triangle that has at least two sides of equal length.

Front

What is an equilateral triangle?

Back

An equilateral triangle is a triangle where all three sides are of equal length.