Using dynamic geometry software

Below, you should be able to see a window which has five tools across the top and a triangle labelled ABC in the main window.
The tools enable you to move and add points, measure and add lines and delete parts of the diagram.

To select a tool, move the cursor over the button and press the left-hand mouse button (known as left-clicking).
A blue border appears around the button to show it has been selected. The name of the tool and its description appears to the right of the toolbar.

Select the 'Move' tool.
Then position the cursor over point A until it is highlighted.
Press the left hand mouse button down and drag the point to a new position. Release the mouse button.
The triangle should change shape.

At the top right of the main window is a 'Reset' button, with two blue arrows.
Left-click on this button to start the diagram again.

To measure a distance in centimetres, select the distance tool and then left-click on the endpoints of the line you want to measure.

Try measuring AB now and then use the 'Move' tool to position the distance label so that it can be seen clearly.

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You can add points to the diagram by selecting the 'New Point' tool and then left-clicking in the window where the new point is required.

To add a line segment, select the 'Segment between two points' tool.
Then left-click on the two endpoints and the line will be drawn between them. You can use existing points or draw the line with two new points.

Try adding a new point and join it to the point B with a line segment.

To delete a point or line, select the 'Delete object' tool.
Then left-click on the point or line to be deleted.
If you delete the new point, the line segment joining it to B will also be deleted.

You will learn how to use other tools as they are needed.

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