1. Section 11-1
Areas of Rectangles

2. Postulate 17
The area of a square is the square of the length of a side.

3. You may also use:

4. Postulate 18: area congruence postulate
If two figures are congruent, then they have the same area.

5. Theorem 11-1
The area of a rectangle equals the product of its base and height.

6. You may also use:

7. Postulate 19: area addition postulate
The area of a region is the sum of its non-overlapping parts.

8. Recall:
An altitude is any segment perpendicular to the line containing the base
The length of an altitude is called the height.

9. True or false? False False
1. If two figures have the same area, then they must be congruent.
False
2. If two figures have the same perimeter, then they must have the same area.
False

10. True or false?
3. If two figures are congruent, then they must have the same area.
True
4. Every square is a rectangle.
True

11. True or false? False True 5. Every rectangle is a square.
6. The base of a rectangle can be any side of the rectangle.
True