Four types of angles: right, obtuse, acute, and straight.

Angles

Four types of angles: right, obtuse, acute, and straight.

A flashcard featuring an illustration of a Straight angle

Flashcard of a Straight angle

A flashcard featuring an illustration of a Straight angle

Illustration used to prove the theorem, "The sum of the angles of any triangle is two right angles."

Sum Of Angles In Triangle Theorem

Illustration used to prove the theorem, "The sum of the angles of any triangle is two right angles."