Proving Circles Similar by APS

Proving Circles are Similar (originally taken from ACCESS student tools CC-BY-SA)[br][br]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. [br][br]Here you have two circles, circle A and Circle B. Use the horizontal and vertical sliders to translate circle B' on the plane. [br][br]Then, use the scale factor slider to adjust the radius of circle B'. [br][br]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?[br][br]2. Are circles always similar? Explain why or why not, using your experiences in this activity.[br][br]3. Before transforming Circle B' turn the 'Show radii' box on. Can you determine the similarity ratio by comparing the radii?[br][br][br][br]

Information: Proving Circles Similar by APS