Investigate various sizes for each of the
different shapes.

- What is the formula for finding the area of a trapezoid? How is the length
of the mid-line involved in the formula?
- What is the formula for finding the area of a parallelogram? How is it
related to the formula for finding the area of a rectangle?
- What is the formula for finding the area of a triangle? How is it related to
the formula for finding the area of a rectangle?