- GeoGebra Materials Team
A DILATION with center D and SCALE FACTOR k is a transformation that maps every point A in the plane to a point A' so that the follwoing properties are true: 1) If A is not the center point D, then the image A' lies on ray DA. The scale factor K is a positive number such that k = ( DA' / DA ), and k ≠1. 2) If A is the center point, the A = A'. The dilation is a REDUCTION if 0 < k < 1 and it is an ENLARGEMENT if k> 1.
Move k along the slider to observe how the scale factor changes the image of the transformation. Try to conclude how the scale factor relates the length of the preimage (a, b, and c) to the lengths of the image (j, l, and m).