Area of polygons

Math

Definition

Formulas for calculating the area enclosed by various polygons. Common formulas include triangle (½bh), rectangle (lw), parallelogram (bh), trapezoid (½(b₁ + b₂)h), and regular polygon (½ · apothem · perimeter).

Examples

  • A triangle with base 10 and height 6 has area ½ · 10 · 6 = 30 square units
  • A trapezoid with parallel sides 8 and 12 and height 5 has area ½(8 + 12)(5) = 50 square units
Key Fact

Triangle: ½bh, Rectangle: lw, Trapezoid: ½(b₁ + b₂)h

Related Terms

Regular polygons Rectangles and squares Parallelogram properties Triangles

Study This Concept

Practice area of polygons with free review games in these units:

Geometry Unit 10: Area and Volume