Copy of Proving Circles Similar by Transformations
Proving Circles are Similar (originally taken from ACCESS student tools CC-BY-SA)
In this sketch we will take the definition of similar to mean that a figure can be translated, rotated, reflected, and dilated completely onto another figure.
Here you have two circles, circle A and Circle B. Use the horizontal and vertical sliders to translate circle B' on the plane.
Then, use the scale factor slider to adjust the radius of circle B'.
Click the blue arrows in the upper left corner to reset the activity with a new pair of circles.
1. Can you transform Circle B' onto Circle A?
2. Are circles always similar? Explain why or why not, using your experiences in this activity.
3. Before transforming Circle B' turn the 'Show radii' box on. Can you determine the similarity ratio by comparing the radii?