Israel Science and Technology Directory

• Formula for perimeter
• Formula for 3D surface area
• Formula for 3D volume

pi (π)=3.1415926535 ...

Area formula for 2D shapes

	Shape	Formula
◯	Circle	pi × radius2
◻	Square	side2
⌷	Rectangle	length × width
▱	Parallelogram	base × height
△	Triangle	base × height / 2
⬠	Regular n-polygon	(1/4) × n × side2 × cot(pi/n)
⏢	Trapezoid	height × (base1 + base2) / 2
⬭	Ellipse	pi × radius1 × radius2

Source: Spiegel, Murray R. Mathematical Handbook of Formulas and Tables.
Schaum's Outline series in Mathematics. McGraw-Hill Book Co., 1968.