Formulas For Area and Perimeter of Shapes
Area of Circle = πr² unit² = π x (length of radius)² Note: π can be approximated by 3.14 or the fraction 22/7
Area of Circle
Area of Triangle = ½ bh unit² = ½ (base) x (height) unit²
Area of Triangle
Area of Parallelogram = bh = (base) x (height) unit²
Area of a Parallelogram
Area of Rectangle = bh unit² = (base) x (height) unit²
Area of a Rectangle
Area of Square = s² unit² = (side length) x (side length) unit²
Area of a Square
Area of a Trapezoid = ½h(b₁ + b₂) unit² = ½ (height) x (top base length + bottom base length)
Area of a Trapezoid
Circumference of a Circle = πd = 2πr = (π) (diameter) = 2 (π) (radius) Note: π can be approximated by 3.14 or the fraction 22/7
Circumference (Perimeter) of a Circle
Perimeter of Parallelogram = 2b + 2l = 2(length of base) + 2(slant height of sides)
Perimeter of Parallelogram
Perimeter of Rectangle = 2L + 2W = 2(side length) + 2(side width)
Perimeter of Rectangle
Perimeter of Square = 4s = 4 (length of one side)
Perimeter of Square
Perimeter of Trapezoid = a + b + c + d = (length base 1) + (length side 1) +(length base 2) + (length side 2)
Perimeter of Trapezoid
Perimeter of Triangle = a + b + c = (length side 1) + (length side 2) + (length side 3)
Perimeter of Triangle
Perimeter of a Regular Polygon = n (side length) where n is the number of sides
Perimeter of a Regular Polygon