1. Draw a line segment and select it and its endpoint. After drawing a line segment, use the "Selection Tool" to drag the mouse to draw a dotted box to select, so that the points and line segments are all inside.

2. Draw a vertical line. Click the menu "Build"-"Vertical Line" to build a vertical line passing through point A and point B.

3. Draw an equal circle. Click the line segment and its endpoints A and B in turn with the mouse, click "Construct"-"Make a circle with the center and radius", and press "Esc" to deselect the circle.

4. Draw three sides of a square. Mark the intersection of vertical line and circle with point tool; Select the line tool to draw three sides of the square.

5. Hide circles and vertical lines. Select the circle and vertical line, and press the shortcut key "Ctrl+H".

Sketchpad is a general teaching environment for mathematics and physics, which is suitable for mathematics, plane geometry and physics. Sketchpad is a teaching software for drawing and animation. Users can write related images and animation processes according to teaching needs. Geometric sketchpad is a dynamic geometric tool, which is suitable for vector analysis and drawing of mathematics, plane geometry and physics, as well as function drawing.

Geometric sketchpad provides rich and convenient creative functions, allowing users to write their own teaching courseware.