GeoGebra Classroom

# Transformations

In this activity, explore the meaning of translations. Select the translate by vector button , select the blue triangle, then select D and E. Change to the arrow tool and drag point E around.
In this activity, explore the meaning of Reflection. Select the reflection button , select the blue triangle, then select line DE. Drag points D or E to change the angle of the line of reflection (mirror) and observe the results. Move the line along the x-axis and observe how the corresponding coordinates are related. Put the line along the y-axis and observe how the corresponding coordinates are related.
In this activity, explore the meaning of Rotation. Select the rotate by angle button . Select the blue triangle and then point D; rotate counterclockwise by 90. Translate the new triangle (A'B'C') in the same manner. Translate the new triangle (A''B''C'') in the same manner.

Follow point A as it is translated to A' and then to A" and finally to A"'. Does this relationship hold for point B and the translated points? Does this relationship hold for point C and the translated points?

In this activity, explore the meaning of Dilation. Currently, triangle ABC is dilated by a factor of 1. Use the slider to change the scale factor and answer the below questions.

How is the shape changed when the dilation factor is 1?

How is the shape changed when the dilation factor is greater than 1?

How is the shape changed when the dilation factor is smaller than 1?