Angles of Triangles

Front

What is an exterior angle of a triangle?

Back

An exterior angle is formed by one side of a triangle and the extension of an adjacent side. It is equal to the sum of the two remote interior angles.

Front

What is a remote interior angle?

Back

A remote interior angle is an angle inside a triangle that is not adjacent to a given exterior angle.

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

How do you classify a triangle with one angle greater than 90 degrees?

Back

A triangle with one angle greater than 90 degrees is classified as an obtuse triangle.

Front

How do you classify a triangle with all angles less than 90 degrees?

Back

A triangle with all angles less than 90 degrees is classified as an acute triangle.

Front

What is an isosceles triangle?

Back

An isosceles triangle is a triangle that has at least two sides of equal length and the angles opposite those sides are equal.

Front

What is a scalene triangle?

Back

A scalene triangle is a triangle in which all three sides are of different lengths and all three angles are of different measures.

Front

What is a right triangle?

Back

A right triangle is a triangle that has one angle measuring exactly 90 degrees.

Front

What is an equiangular triangle?

Back

An equiangular triangle is a triangle in which all three angles are equal, and each angle measures 60 degrees.

Front

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

Back

The other two angles must be acute, and their measures must add up to 90 degrees.