13 terms

Acute Angle

An angle that measures less than 90°

Right Angle

An angle that measures exactly 90°

Obtuse Angle

An angle that measures more than 90° and less than 180°

Straight Angle

An angle that measures exactly 180°

Vertex

A corner or a point where two or more straight lines (or rays) meet.

Equilateral Triangle

A triangle that has 3 equal sides.

Isosceles Triangle

A triangle in which two sides are the same, while the other side is different

Scalene Triangle

A triangle with no equal sides

Acute Triangle

A triangle with 3 acute angles

Obtuse Triangle

A triangle with one obtuse angle.

Right Triangle

A triangle with one right angle.

Perimeter

The distance around a shape.

Polygon

A closed plane figure made up of line segments.