4.5. Rotations with GeoGebra
Choose any point A in the plane (it is recommended to center it on the screen). This exercise will work on rotating by an angle of 100° (clockwise) around point A.
a) Draw a trapezoid far from the point and use the “Rotation” tool in GeoGebra to rotate the trapezoid by 100° (clockwise) around point A. Analyze if the result makes sense to you.
b) We are going to verify that the definition seen in class holds. To do this, take any vertex of the trapezoid (let's call it B). Use the “Line”, “Angle”, and “Compass” tools to manually find the point B' that results from rotating B around A. Follow the steps used in class:
- Draw the line r that connects A and B (using the “Line” tool).
- Draw a line s that forms a 100° angle (clockwise) with the line that connects A and B (using the “Angle” and “Line” tools)
- Use the “Compass” tool to find B' on line s, such that |AB'| = |AB|.