Formulas for Perimeter, Area and Volume

Concept sheet | Mathematics

There are several formulas that can be used to calculate the perimeter and area of plane figures, as well as the area and volume of solids. Each of these formulas can be used to find a missing measurement in a figure or a missing measurement in a solid.

Formulas for Plane Figures

Definitions
  • The perimeter, generally denoted |P,| is the length of the contour of a figure. In the case of the circle, the perimeter is called “circumference” and is denoted |C.|

  • The area, generally denoted |A,| is the surface delimited by a figure.

Plane Figure

Perimeter

Area

Triangle

Triangle with 3 sides and a height identified

||P=\color{#3A9A38}{\boldsymbol{a}}+\color{#3B87CD}{\boldsymbol{b}}+\color{#FF55C3}{\boldsymbol{c}}||

||A=\dfrac{\color{#3B87CD}{\boldsymbol{b}}\times\color{#EC0000}{\boldsymbol{h}}}{2}||

Square

Square with 4 sides identified

||\begin{align}P&=\color{#3A9A38}{\boldsymbol{s}}+\color{#3A9A38}{\boldsymbol{s}}+\color{#3A9A38}{\boldsymbol{s}}+\color{#3A9A38}{\boldsymbol{s}}\\&=4\color{#3A9A38}{\boldsymbol{s}}\end{align}||

||\begin{align}A&=\color{#3A9A38}{\boldsymbol{s}}\times\color{#3A9A38}{\boldsymbol{s}}\\&=\color{#3A9A38}{\boldsymbol{s}}^2\end{align}||

Rectangle

Rectangle with 2 bases and 2 heights identified

||\begin{align}P&=\color{#3B87CD}{\boldsymbol{b}}+\color{#3B87CD}{\boldsymbol{b}}+\color{#EC0000}{\boldsymbol{h}}+\color{#EC0000}{\boldsymbol{h}}\\&=2\color{#3B87CD}{\boldsymbol{b}}+2\color{#EC0000}{\boldsymbol{h}}\\&=2(\color{#3B87CD}{\boldsymbol{b}}+\color{#EC0000}{\boldsymbol{h}})\end{align}||

||A=\color{#3B87CD}{\boldsymbol{b}}\times\color{#EC0000}{\boldsymbol{h}}||

Parallelogram

Parallelogram with 2 pairs of sides and a height identified

||\begin{align}P&=\color{#FF55C3}{\boldsymbol{a}}+\color{#FF55C3}{\boldsymbol{a}}+\color{#3B87CD}{\boldsymbol{b}}+\color{#3B87CD}{\boldsymbol{b}}\\&=2\color{#FF55C3}{\boldsymbol{a}}+2\color{#3B87CD}{\boldsymbol{b}}\\&=2(\color{#FF55C3}{\boldsymbol{a}}+\color{#3B87CD}{\boldsymbol{b}})\end{align}||

||A=\color{#3B87CD}{\boldsymbol{b}}\times\color{#EC0000}{\boldsymbol{h}}||

Rhombus

Rhombus with 2 diagonals and 4 sides identified

||\begin{align}P&=\color{#3A9A38}{\boldsymbol{s}}+\color{#3A9A38}{\boldsymbol{s}}+\color{#3A9A38}{\boldsymbol{s}}+\color{#3A9A38}{\boldsymbol{s}}\\&=4\color{#3A9A38}{\boldsymbol{s}}\end{align}||

||A=\dfrac{\color{#FF55C3}{\boldsymbol{D}}\times\color{#3B87CD}{\boldsymbol{d}}}{2}||

Trapezoid

Trapezoid with 2 bases, 2 sides and a height identified

||P=\color{#3B87CD}{\boldsymbol{b}}+\color{#3A9A38}{\boldsymbol{a}}+\color{#FA7921}{\boldsymbol{B}}+\color{#FF55C3}{\boldsymbol{c}}||

||A=\dfrac{(\color{#3B87CD}{\boldsymbol{b}}+\color{#FA7921}{\boldsymbol{B}})\times\color{#EC0000}{\boldsymbol{h}}}{2}||

Regular Polygon

Regular polygon with n sides and an apothem identified

||P=n\times\color{#3A9A38}{\boldsymbol{s}}||

||A=\dfrac{\color{#3A9A38}{\boldsymbol{s}}\color{#FA7921}{\boldsymbol{a}}n}{2}||

Circle

Circle with a radius identified

||C=2\pi\color{#3A9A38}{\boldsymbol{r}}||

||A=\pi\color{#3A9A38}{\boldsymbol{r}}^2||

Formulas for Solids

Definitions
  • The area of the base, generally denoted |A_b,| is the surface occupied by the figure(s) that serve as base for a solid.

  • The lateral area, generally denoted |A_L,| is the surface occupied by the figures that do not serve as base for a solid.

  • The total area, generally denoted |A_T,| is the surface occupied by all the figures forming a solid.

  • The volume, generally denoted |V,| is the space delimited by the faces of a solid.

​Solid

Area Formula

​Volume Formula

​​Cube

Cube with a side identified

Area of Cubes||\begin{align}A_b&=\color{#3a9a38}{\boldsymbol{s}}^2\\\\ A_L&=4\color{#3a9a38}{\boldsymbol{s}}^2\\\\A_T&=6\color{#3a9a38}{\boldsymbol{s}}^2\end{align}||

Volume of Cubes||V=\color{#3a9a38}{\boldsymbol{s}}^3||

Prism

Prism with a height identified

Area of Prisms||\begin{align}\color{#3b87cd}{\boldsymbol{A_b}}&=\text{relevant formula}\\\\A_L&=P_b\times\color{#ec0000}{\boldsymbol{h}}\\\\A_T&=A_L+2\color{#3b87cd}{\boldsymbol{A_b}}\end{align}||

Volume of Prisms||V=\color{#3b87cd}{\boldsymbol{A_b}}\times\color{#ec0000}{\boldsymbol{h}}||

Pyramid

Pyramid with a height and an apothem identified

Area of Pyramids||\begin{align}\color{#3b87cd}{\boldsymbol{A_b}}&=\text{relevant formula}\\\\A_L&=\dfrac{P_b\times\color{#fa7921}{\boldsymbol{a}}}{2}\\\\A_T&=A_L+\color{#3b87cd}{\boldsymbol{A_b}}\end{align}||

Volume of Pyramids||V=\dfrac{\color{#3b87cd}{\boldsymbol{A_b}}\times\color{#ec0000}{\boldsymbol{h}}}{3}||

Sphere

Sphere with a radius identified

Area of Spheres||A_T=4\pi\color{#3a9a38}{\boldsymbol{r}}^2||

Volume of Spheres||V=\dfrac{4\pi\color{#3a9a38}{\boldsymbol{r}}^3}{3}||

Cylinder

Cylinder with a height and radius identified

Area of Cylinders||\begin{align}\color{#3b87cd}{\boldsymbol{A_b}}&=\pi\color{#3a9a38}{\boldsymbol{r}}^2\\\\A_L&=2\pi\color{#3a9a38}{\boldsymbol{r}}\color{#ec0000}{\boldsymbol{h}}\\\\A_T&=A_L+2\color{#3b87cd}{\boldsymbol{A_b}}\end{align}||

Volume of Cylinders||V=\color{#3b87cd}{\boldsymbol{A_b}}\times\color{#ec0000}{\boldsymbol{h}}||

Cone

Cone with a height and radius identified

Area of Cones|​​|\begin{align}\color{#3b87cd}{\boldsymbol{A_b}}&=\pi\color{#3a9a38}{\boldsymbol{r}}^2\\\\A_L&=\pi\color{#3a9a38}{\boldsymbol{r}}\color{#fa7921}{\boldsymbol{a}}\\\\A_T&=A_L+\color{#3b87cd}{\boldsymbol{A_b}}\end{align}||

Volume of Cones||V=\dfrac{\color{#3b87cd}{\boldsymbol{A_b}}\times\color{#ec0000}{\boldsymbol{h}}}{3}||