POLYGONS

BUILDING POLYGONS

We use line segments to build polygons.

A polygon is a closed shape with straight sides.

POLYGON NOT A POLYGON

POLYGONS

POLYGONS

Polygons may also be called 2D shapes or PLANE

FIGURES. A PLANE is a flat surface. PLANE figures are flat, not solid or 3D.

Is it a polygon?

U

ATTRIBUTES are characteristics or traits of a polygon or shape, such as:

•The number of sides•The number of angles (corners)•The length of sides•The number of right angles

Compare and contrast.What attributes are the same? What are different?

triangle

rectangle

square

Some polygons have special names.

quadrilateral

pentagon

hexagon

octagon

Some polygons have special names.

triangle

rectangle square

Let’s take a closer look at some special shapes.

circleAre they all polygons?

What letter is inside the circle and the triangle?

What letter is inside the rectangle but NOT in the circle?

What letters are inside the triangle but outside the square?

A BC

D

EF

triangle

rectangle

square

circle

A circle is a PLANE (flat) figure but not a polygon. It does not have straight sides.