Here is a picture of a bicycle:
Which one of the pictures below looks like a reasonable scale model of the above bicycle?
We are doing to use dilation to make our scale models and then check that they have the scale ratio in question. Dilation is another transformation, but unlike rotation, reflection, and translation, it is not a rigid motion. Therefore it does not make a congruent image.
Try to scale this by a factor of 1/2:
Dilation can be used to make scale versions of figures. If a figure is a scale version of another figure than we say that they are similar. We use the ~ to denote similarity.
Watch the videos below to help you remember how to do dilations with a compass and straight edge.
Check out this more challenging construction:
And one more: