1. 1.8 Perimeter, circumference, and area

2. Perimeter (P) of a polygon is the sum of the length of the sides.
Area (A) of a polygon is the number of square units it encloses. Some shapes have basic formulas that you may already be familiar with

4. Many times the exact answer is preferred but other times the calculator/rounded version is easier to understand and visualize. And is more applicable to real live situations. Usually the exact answer will be preferred if the amount will be used in additional calculations.

5. You can find area and perimeter within the coordinate plane as well
Must be able to use the distance formula to do this.
Can you also find the area of this triangle? CAN THIS BE DONE FOR ANY THREE NON-COLLINEAR POINTS?

6. Areas of irregular shapes.
Often we encounter shapes that are not simple quadrilaterals or regular polygons. These shapes are said to be IRREGULAR. The antithesis of REGULAR.
Break the shape on the left into multiple nonoverlapping parts. Think ahead of what shapes you want your parts to be, make sure that the individual parts become shapes in which you have a basic formula to find the area for.

7. Homework
Section 1.8 in MathXLforSchool.com

8. Examples