Triangle Properties and Theorems

Front

What is the relationship between the angles and sides of a triangle?

Back

In a triangle, the smallest angle is opposite the smallest side, and the largest angle is opposite the largest side.

Front

What is the Triangle Inequality Theorem?

Back

The sum of the lengths of any two sides of a triangle must be greater than the length of the third side.

Front

How can you determine if three lengths can form a triangle?

Back

Use the Triangle Inequality Theorem: For lengths a, b, and c, check if a + b > c, a + c > b, and b + c > a.

Front

What type of triangle has all angles less than 90 degrees?

Back

An acute triangle.

Front

What type of triangle has one angle greater than 90 degrees?

Back

An obtuse triangle.

Front

What is a scalene triangle?

Back

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

Front

What is an isosceles triangle?

Back

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

Front

What is an equilateral triangle?

Back

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

Front

What is an exterior angle of a triangle?

Back

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

Front

What are remote interior angles?

Back

Remote interior angles are the two angles inside a triangle that are not adjacent to a given exterior angle.