a face.
An octagon.
An angle on the coordinate plane
An octagon.
a face
An 8-sided plane figure is an octagon.
a face.
An octagon.
The plane.
An angle on the coordinate plane
An octagon.
octagon
perimeter
a face
The distance around a closed plane figure is called the perimeter. The perimeter of a figure can be calculated by adding together the lengths of each side.
octahedron
A plane figure