Problem:

A triangle is dilated with a scale factor of ½. 

If the perimeter of the original shape is 24’, what is the perimeter of the new triangle?

Explain your reasoning and give an example of an original triangle and a dilated triangle that supports your answer.

Answer:

The perimeter of the image will be 12’ because the perimeter is changed by the scale factor. 

Example: 

The sides of the original triangle could have been 6’, 8’, and 10’. 

The sides of the dilated triangle will be 3’, 4’, and 5’ which results in a perimeter of 12’.