Triangle Properties

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 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 defines an equilateral triangle?

Back

An equilateral triangle has all three sides of equal length and all three interior angles equal to 60 degrees.

Front

What is an acute triangle?

Back

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

Front

What is a scalene triangle?

Back

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

Front

What is an isosceles triangle?

Back

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

Front

What is a right triangle?

Back

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

Front

What is a corresponding angle?

Back

Corresponding angles are pairs of angles that are in similar positions at each intersection where a straight line crosses two others.

Front

What is a remote interior angle?

Back

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

Front

How do you classify triangles based on angles?

Back

Triangles can be classified as acute (all angles < 90°), right (one angle = 90°), or obtuse (one angle > 90°).