#### Understanding

Students should recognize that lengths scale by a linear scale factor, but areas scale by the square of the scale factor that relates the lengths (if the area is measured in the unit of measurement derived from that used for length).

### What to look for

Have students examine the internal ratios between each shape as another way to make a connection of the ratio to scaling shapes.### Sample Assessment

If the Rectangle S is an enlarged copy of Rectangle R, what is the scale factor?

Answer: 3