# Planar Figures, Perimeter (Circumference) and Area in GeoGebra

You can use `GeoGebra` to draw points, lines, and planar figures like polygons, circles, and ellipses. You’ll also learn how you can compute the perimeter/circumference and area of your figures.

`GeoGebra` Instruction 1

### DrawingaPoint

1.
Open `Algebra View` and `Graphics View` under  `View` in  `Menu`.
2.
Select the `Point`  tool, which is the second tool in `Toolbar`.
3.
Draw a point in `Graphics View` by clicking on where you want your point.
4.
If you want to hide the axes and the grid lines in `Graphics View`, click `Style Bar`  in the top-right corner. Click the left-most button to hide the axes. To hide the grid, click the button showing a grid, then select the option which has no grid lines.

`GeoGebra` Instruction 2

### DrawingaLine

1.
Open `Algebra View` and `Graphics View` under  `View` in  `Menu`.
2.
Select the `Line`  tool, which is the third tool in `Toolbar`.
3.
Lines in `GeoGebra` are made by first drawing two points, then `GeoGebra` draws the line that goes through them both. Like in Item 4, make the points by clicking on where you want them.
4.
If you click the `Line`  tool again, you’ll open the `toolbox` for lines. Here you’ll find many alternatives to `Line` :

• The second tool in the list is `Segment` , which lets you draw a line segment between two existing points.

• The third tool in the list lets you draw a line segment with a given length.

5.
If you want to hide the axes and the grid lines in `Graphics View`, click `Style Bar`  in the top-right corner. Click the left-most button to hide the axes. To hide the grid, click the button showing a grid, then select the option which has no grid lines.

`GeoGebra` Instruction 3

### DrawingaPolygon

1.
Open `Algebra View` and `Graphics View` under  `View` in  `Menu`.
2.
Select the `Polygon`  tool, which is the fifth tool in `Toolbar`.
3.
Draw a polygon by clicking on where you want its vertices to be. When you’ve drawn all the vertices, complete the polygon by clicking on the first vertex you drew.
4.
If you want to hide the axes and the grid lines in `Graphics View`, click `Style Bar`  in the top-right corner. Click the left-most button to hide the axes. To hide the grid, click the button showing a grid, then select the option which has no grid lines.

`GeoGebra` Instruction 4

### FindingthePerimeter/CircumferenceofaFigure

1.
Draw your figure in `GeoGebra`.

2.
Find the name of your figure in `Algebra View`. Usually, the first polygon gets the name `t1`, while circles and ellipses get the name `c`.
3.
In an empty row in `Algebra View`, use the command

• `Perimeter(<Polygon>)` if your figure is a polygon. Replace `<Polygon>` by the name you got in Step 2.

• `Circumference(<Conic>)` if your figure is a circle or an ellipse. Replace `<Conic>` by the name you got in Step 2.

Press `Enter`. The perimeter/circumference will be printed in `Algebra View`.

`GeoGebra` Instruction 5

### FindingtheAreaofaFigure

1.
Draw your figure in `GeoGebra`.

2.
Find the name of your figure in `Algebra View`. Usually, first polygon gets the name `t1`, while circles and ellipses get the name `c`.
3.
In an empty row in `Algebra View`, use the command

• `Area(<Polygon>)` if your figure is a polygon. Replace `<Polygon>` by the name you got in Step 2.

• `Area(<Conic>)` if your figure is a circle or an ellipse. Replace `<Conic>` by the name you got in Step 2.

Press `Enter`. The area will be printed in `Algebra View`.