Polygons

Polygon Triangle Quadrilateral Pentagon Hexagon Heptagon Octagon Nonagon Decagon Sides 3 4 5 6 7 8 9 10 Angles 3 4 5 6 7 8 9 10 Vertices 3 4 5 6 7 8 9 10 Note: polygons with more than 10 sides are usually called an “n-gon”. For example a 15-gon has 15 sides. Polygon: … Read more

Congruent vs Similar

If the shapes being compared are exactly equal in size and shape, then they are congruent. Congruent sides or segments have the exact same length. Congruent angles have the exact same measure. Note: Congruent segments, sides, and angles are often marked. Example:  If the shapes being compared are exactly the same shape but not same size, then they are similar. Example:

Angles

Angle type Degrees Example Acute 1° – 89° Right 90° Obtuse 91° – 179° Straight 180° Full Rotation “Circle” 360° Every triangle is made up of 180°, and every quadrilateral is made up of 360°.