Draw a parallelogram, a triangle, and a trapezoid that each have areas of 16cm2
parallelogram: A = bh
triangle: A = 1/2 bh
trapezoid: A = (b1 + b2)/2 * h
so think of the pairs of factors of 16: 1,2,4,8,16
use one for the height and the other to figure the base(s)
Note that a triangle is just a trapezoid with one base = 0