QZ GEOM: Triangle Basics

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°.

Front

What type of triangle has all sides of equal length?

Back

An equilateral triangle has all sides of equal length.

Front

What is an isosceles triangle?

Back

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

Front

What is a scalene triangle?

Back

A scalene triangle has all sides of different lengths.

Front

What is a right triangle?

Back

A right triangle has one angle that measures 90°.

Front

How do you find the measure of an unknown angle in a triangle?

Back

Use the formula: m∠A + m∠B + m∠C = 180°.

Front

What is the definition of an obtuse triangle?

Back

An obtuse triangle has one angle that measures more than 90°.

Front

What is the Pythagorean theorem?

Back

In a right triangle, a² + b² = c², where c is the hypotenuse.

Front

What is the relationship between the angles in an isosceles triangle?

Back

The angles opposite the equal sides are also equal.

Front

What is the exterior angle theorem?

Back

The exterior angle of a triangle is equal to the sum of the two opposite interior angles.