Geometry formulas and equations

The formulas listed below are commonly required in geometry to calculate lengths, areas and volumes. You can use these to help with your children's math homework.

List of formulas

Area of Square = length2 (l x l)
a square with sides of length, l
Area of Rectangle = length x height
a rectangle with a width of l and a height of h
Area of Triangle = 1/2 x length x height
a triangle with length of l and height of h
Area of circle

= 𝛑r2

(𝛑 = 3.14 approximately)
a circle with radius of r shown
Circumference of a circle circumference = 2 r
(𝛑 x diameter)
Volume of rectangular prism = length x height x depth
a 3D representation of a rectangular prism with sides of length d,l, and h
Volume of cylinder

= area of base x height

= 𝛑 (d/2)2 x h

a 3D representation of a cylinder with a diameter d and a height of h.
Volume of cone

= 1/3 x area of base x height

= 1/3 x 𝛑(d/2)2 x h

a 3D representation of a cone with a diameter d and a height of h.

More Math Help

All Geometry 24 Worksheets Terms/ Definitions Formulas/ Equations 2D Shapes 3D Shapes Quadrilaterals Measuring Angles Using a Protractor Adding and Subtracting Angles Angle Properties Finding Angles Symmetry Area Volume Surface Area Perimeter Coordinate System Coordinate Graphing Pythagoras' Theorem Distance Between Two Points Congruent Triangles Similar Triangles Transformations Dilations

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