Flat surfaces such as walls, desk tops, floors, and paper are planes. Planes are everywhere around you.
A flat, closed figure that is in a plane is called a plane figure. A plane figure can be made of straight lines, curved lines, or both straight and curved lines.

Look at the figures and click on the ones that are plane figures. Remember that a plane figure is closed and has straight or curved lines.

Look at these figures and decide if they are made of straight lines, curved lines or both straight and curved lines.
curved
straight
both
curved
straight
both
curved
straight
both
curved
straight
both

Some letters of the alphabet are plane figures. See if you can decide which letters are plane figures. Remember that a plane figure is a flat, closed, shape in a plane.
Click on the letters you think are plane figures.

All of these everyday shapes are plane figures.

Some
plane figures
have all straight sides and angles. The number of sides and angles will be the same.

Look at the following figures and tell how many sides and angles each one has.
Sides:
1
2
3
4
5
6
7
8
Angles:
1
2
3
4
5
6
7
8
Sides:
1
2
3
4
5
6
7
8
Angles:
1
2
3
4
5
6
7
8
Sides:
1
2
3
4
5
6
7
8
Angles:
1
2
3
4
5
6
7
8
Sides:
1
2
3
4
5
6
7
8
Angles:
1
2
3
4
5
6
7
8
Sides:
1
2
3
4
5
6
7
8
Angles:
1
2
3
4
5
6
7
8
Sides:
1
2
3
4
5
6
7
8
Angles:
1
2
3
4
5
6
7
8
Sides:
1
2
3
4
5
6
7
8
Angles:
1
2
3
4
5
6
7
8
Sides:
1
2
3
4
5
6
7
8
Angles:
1
2
3
4
5
6
7
8

Now let’s see if you can find out how many lines and angles are in these everyday objects. Type in the number of lines and the number of angles.
Sides:
0
1
2
3
4
5
6
7
8
Angles:
0
1
2
3
4
5
6
7
8
Sides:
0
1
2
3
4
5
6
7
8
Angles:
0
1
2
3
4
5
6
7
8
Sides:
0
1
2
3
4
5
6
7
8
Angles:
0
1
2
3
4
5
6
7
8

Plane figures are flat, closed, figures that are in a plane. Look around your room for plane figures. Get a sheet of paper and draw and label 4 plane figures with 4 different shapes.
Plane figures are all around you !
