Polygon f has an area of 36 square units. aimar drew a scaled version of polygon f and labeled it polygon g. polygon g has an area of 4 square units. what scale factor did aimar use to go from polygon f to polygon g?

Area is a squared number.  We know that from the label we use when we solve problems involving area.  Perimeter is a single unit label.  This single unit label can also be used to find scale factor, since single unit labels are one-to-one.  If the area of polygon F is 36, that means that the single unit measure was a number that was squared to get to the area.  Same goes for polygon G.  That means that in order to find the single unit measure of each of those we have to take the square root of the area.  The square root of 36 is 6, and the square root of 4 is 2.  6:2 is the scale factor, but that can be reduced to 3:1, larger to smaller.

She should use 12/3 to measure