In the below activity the blue shape has been enlarged about the green point by a scale factor of 2 to produce the green shape.
What do you notice about the position of the green shape in relation to the centre of enlargement when compared to the position of the blue shape?
Move the green point to change the centre of enlargement. What has happened to the position of the green shape?
What will happen to the green shape if you move the red vertex of the blue shape one square to the right?
Use the slider to change the scale factor of the enlargement. Make the factor 3. What has happened to the position of the green shape?
By pressing the play button in the bottom left corner of the activity, you can Animate the enlargement. Either manually adjust the factor using the slider, or use an animation. What happens as the factor changes?
Use the pen tool to draw the following enlargements of the purple shape:
How did you do it?
Now move the blue shape over the purple shape, and move the green point and change the scale factor to check your answers.
What information do you need to fully describe an enlargement?
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