In previous grades, you learned that the area of a figure is the amount of flat space that the figure covers. Area is measured in square units, such as square inches or square centimeters.

The area of a rectangle is determined by counting the number of square units in one row of the rectangle and multiplying by the number of rows. You can also use the area formula for a rectangle, A = bh, where b is the base length of the rectangle, or the number of square units in one row, and h is the height of the rectangle, or the number of rows.

Other polygons also have area formulas. You can use modeling to show the area formulas of a parallelogram, triangle, and trapezoid.

Use the interactive below to review the area formulas for a rectangle, square, parallelogram, triangle, and trapezoid. Click on the name of the polygon to see a picture and the area formula for that polygon.

In this lesson, you will use the area formulas to solve application problems. In doing so, you may encounter fractions and decimals, so you may need to review multiplication and division of fractions. You may also need to review how to convert between fractions and decimals in order to perform computations with rational numbers.

Click on the conversion you want to perform to see more information about how to perform that conversion.