Relationships in Triangles

Front

What do the angles in an equilateral triangle measure?

Back

60°, 60°, 60°

Front

What is the Exterior Angle Theorem?

Back

The Exterior Angle Theorem states that the measure of an exterior angle is equal to the sum of the measures of the two non-adjacent interior angles.

Front

If one angle of a triangle measures 50° and another measures 60°, what is the measure of the third angle?

Back

70°

Front

What is the sum of the interior angles of a triangle?

Back

180°

Front

In a right triangle, what is the relationship between the angles?

Back

One angle measures 90°, and the other two angles are complementary (sum to 90°).

Front

What is the Pythagorean Theorem?

Back

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

Front

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

Back

Subtract the sum of the known angles from 180°.

Front

What is an isosceles triangle?

Back

A triangle with at least two sides of equal length.

Front

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

Back

The angles opposite the equal sides are also equal.

Front

If two angles of a triangle are 45° and 55°, what is the measure of the third angle?

Back

80°