UNIT 6
Area and Volume
LESSON 5
Area of Polygons
In this lesson, we will learn about finding the area of polygons. A polygon is a closed figure with straight sides. The area of a polygon is the amount of space inside it.
To find the area of a polygon, we use different formulas depending on the type of polygon. Here are some common polygons and their area formulas:
1. Square: A square is a polygon with four equal sides. The formula to find the area of a square is:
Area = side x side (or side^2)
2. Rectangle: A rectangle is a polygon with opposite sides equal and all angles equal to 90 degrees. The formula to find the area of a rectangle is:
Area = length x width
3. Triangle: A triangle is a polygon with three sides. The formula to find the area of a triangle depends on the type of triangle. For a right triangle, the formula is:
Area = 0.5 x base x height
4. Parallelogram: A parallelogram is a quadrilateral with opposite sides parallel and equal in length. The formula to find the area of a parallelogram is:
Area = base x height
5. Trapezoid: A trapezoid is a quadrilateral with one pair of parallel sides. The formula to find the area of a trapezoid is:
Area = 0.5 x sum of bases x height
6. Regular Polygon: A regular polygon is a polygon with all sides and angles equal. The formula to find the area of a regular polygon is:
Area = 0.5 x perimeter x apothem
To find the area of a polygon, plug the given measurements (e.g. side lengths, bases, heights) into the appropriate formula. Remember to follow the order of operations (PEMDAS) when performing calculations.
Practice finding the area of different polygons to become more comfortable with the formulas and calculations. Remember that practice makes perfect, so keep practicing to improve your skills in finding the area of polygons.