Math Goodies is a free math help portal for students, teachers, and parents.
|
Free Math

Interactive Math Goodies Software

 Area of a Parallelogram Unit 1 > Lesson 3 of 8

 The area of a polygon is the number of square units inside the polygon. Area is 2-dimensional like a carpet or an area rug. A parallelogram is a 4-sided shape formed by two pairs of parallel lines. Opposite sides are equal in length and opposite angles are equal in measure. To find the area of a parallelogram, multiply the base by the height. The formula is: where is the base, is the height, and · means multiply. The base and height of a parallelogram must be perpendicular. However, the lateral sides of a parallelogram are not perpendicular to the base. Thus, a dotted line is drawn to represent the height. Let's look at some examples involving the area of a parallelogram. Example 1: Find the area of a parallelogram with a base of 12 centimeters and a height of 5 centimeters. Solution: = (12 cm) · (5 cm) = 60 cm2 Example 2: Find the area of a parallelogram with a base of 7 inches and a height of 10 inches. Solution: = (7 in) · (10 in) = 70 in2 Example 3: The area of a parallelogram is 24 square centimeters and the base is 4 centimeters. Find the height. Solution: 24 cm2 = (4 cm) · 24 cm2 ÷ (4 cm) = = 6 cm Summary: Given the base and height of a parallelogram, we can find the area. Given the area of a parallelogram and either the base or the height, we can find the missing dimension. The formula for area of a parallelogram is: where is the base, is the height, and · means multiply.

### Exercises

 Directions: Read each question below. Click once in an ANSWER BOX and type in your answer; then click ENTER. Your answers should be given as whole numbers greater than zero. After you click ENTER, a message will appear in the RESULTS BOX to indicate whether your answer is correct or incorrect. To start over, click CLEAR.

 1 Find the area of a parallelogram with a base of 8 feet and a height of 3 feet. ANSWER BOX:   = ft2 RESULTS BOX:

 2 Find the area of a parallelogram with a base of 4 meters and a height of 9 meters. ANSWER BOX:   = m2 RESULTS BOX:

 3 The area of a parallelogram is 64 square inches and the height is 16 inches. Find the base. ANSWER BOX:   = in RESULTS BOX:

 4 A parallelogram has an area of 54 square centimeters and a base of 6 centimeters. Find the height. ANSWER BOX:   = cm RESULTS BOX:

 5 A parallelogram-shaped garden has an area of 42 square yards and a height of 6 yards. Find the base. ANSWER BOX:   = yd RESULTS BOX:

This lesson is by Gisele Glosser. You can find me on Google.

 Perimeter & Area Unit Perimeter of Polygons Area of Rectangles Area of Parallelograms Area of Triangles Area of Trapezoids Practice Exercises Challenge Exercises Solutions

 Related Activities Geometry and a Shoebox Geometry Worksheet Generator Perimeter and String Polygon Crossword Puzzles Pre-Made Worksheets

More Math Help:
 Grants Online Degrees