Identify the shape (rectangle, triangle, circle, trapezoid, parallelogram, etc.)
Use the correct area formula for that shape
Substitute the given measurements into the formula
Calculate the result
Include the correct square units (e.g., cm², m², in²)
If units are mixed, convert them to the same unit before calculating
Rectangle: A = length × width
Square: A = side²
Triangle: A = base × height ÷ 2
Parallelogram: A = base × height
Trapezoid: A = (base1 + base2) × height ÷ 2
Circle: A = πr²
Semicircle: A = (πr²) ÷ 2
Annulus (ring): A = π(R² − r²)
Regular polygon: A = (perimeter × apothem) ÷ 2
Irregular shape (grid method): A = (number of full squares × area of one square) + (fractional squares × area of one square)
Irregular shape (split method): Divide into known shapes, find each area, then add them