## Area of 2D Shapes Formulas

This document provides formulas for calculating the area of common two-dimensional (2D) shapes.

**What is Area?**

Area is the amount of space a two-dimensional shape covers. It is measured in square units, such as square centimeters (cm²) or square inches (in²).

**Formulas for Common 2D Shapes:**

**1. Square**

**Formula:**Area = side * side**Where:**- side = length of one side of the square

**2. Rectangle**

**Formula:**Area = length * width**Where:**- length = length of the rectangle
- width = width of the rectangle

**3. Triangle**

**Formula:**Area = (1/2) * base * height**Where:**- base = length of the base of the triangle
- height = perpendicular distance from the base to the opposite vertex

**4. Parallelogram**

**Formula:**Area = base * height**Where:**- base = length of the base of the parallelogram
- height = perpendicular distance between the base and the opposite side

**5. Trapezoid**

**Formula:**Area = (1/2) * (base1 + base2) * height**Where:**- base1 = length of one base of the trapezoid
- base2 = length of the other base of the trapezoid
- height = perpendicular distance between the two bases

**6. Circle**

**Formula:**Area = π * radius²**Where:**- π (pi) ≈ 3.14159
- radius = distance from the center of the circle to any point on the circumference

**7. Ellipse**

**Formula:**Area = π * a * b**Where:**- π (pi) ≈ 3.14159
- a = length of the semi-major axis
- b = length of the semi-minor axis

**8. Regular Polygon**

**Formula:**Area = (1/2) * perimeter * apothem**Where:**- perimeter = total length of all sides of the polygon
- apothem = distance from the center of the polygon to the midpoint of a side

**Example:**

**Calculate the area of a rectangle with a length of 8 cm and a width of 5 cm.**

- Area = length * width
- Area = 8 cm * 5 cm
- Area =
**40 cm²**

**Using the Formulas**

**Identify the shape.****Measure the required dimensions.****Substitute the values into the appropriate formula.****Calculate the area.**

By using these formulas, you can easily calculate the area of various 2D shapes.