# Segments and Midpoint

- Author:
- Jorge Cássio

- Topic:
- Line Segment

## Constructing midpoint of line segment AB

In the following GeoGebra applet, follow the steps below:
-Select the **COMPASS tool (Window 5)**. Then click on line segment CD (represents the opening length of the compass) and then on the point **A**. Then click on line segment CD (represents the opening length of the compass) and then on the point **B. **
-Select the **INTERSECT (Window 3)** and mark the intersections **E** and **F **of the two circles.
- Select the **SEGMENT tool (Window 4) **and draw a line segment with endpoints** E **and **F.**
-** **Select the INTERSECT **tool (Window 3)** and mark the intersection of line segments **AB** and **EF**. Change the name of the point to **M.** -
Select the **SHOW/HIDE OBJECT tool (Window 6)** and hide the circles and the line segment **EF**, leaving only the line segment **AB** and the point **M.**
**NOTE**: you can hide the objects by clicking on it with the right button and choosing the option "Show object".
- Select the tool **DISTANCE OR LENGTH (Window 7)** and click on **A** and then on **M**. Then click on **B** and then on **M.** What do you see? What is a “Midpoint”? Points **A** and **B** are said to be symmetric in relation
to point **M**, which is considered the center of symmetry.
- Select the tool **MOVE (Window 1)** move point **A** or **B.** Observe.