Math - 2018-19
3.8 - Perimeter and Area
The student will
a) estimate and measure the distance around a polygon in order to determine its perimeter using U.S. Customary and metric units; and
b) estimate and count the number of square units needed to cover a given surface in order to determine its area.
So that I can measure my back yard to find out how much fencing is needed to close it in
- So that I can determine how much paint is needed to paint my bedroom
UNDERSTANDING THE STANDARD
- A polygon is a closed plane figure composed of at least three line segments that do not cross. A plane figure is any closed, two-dimensional shape.
- Perimeter is the path or distance around any plane figure.
- Area is the number of iterations of a two-dimensional unit needed to cover a surface. The two-dimensional unit is usually a square, but it could also be another shape such as a rectangle or an equilateral triangle.
- The unit of measure used to find the perimeter or area is stated along with the numerical value when expressing the perimeter or area of a figure (e.g., the perimeter of the book cover is 38 inches and the area of the book cover is 90 square inches).
- Opportunities to explore the concepts of perimeter and area should involve hands-on experiences (e.g., placing toothpicks (units) around a polygon and counting the number of toothpicks to determine its perimeter and filling or covering a polygon with tiles (square units) and counting the tiles to determine its area).
The student will use problem solving, mathematical communication, mathematical reasoning, connections, and representations to