Question

Sometimes a dilation is an enlargement, and sometimes it is a reduction. Explain what types of numbers for scale factors causes each.

Answer 1

If your scale factor has absolute value greater than 1, the dilation is an enlargement. 
If your scale factor has abs value less than 1, the dilation is a reduction. 
If the scale factor is equal to 1, the image is congruent to the preimage. 

Hope this helps.