A rectangular prism is a three-dimensional object characterized by six rectangular faces, two of which are considered to be the bases of the prism. Rectangular prisms are commonly seen in the real world in the form of cardboard boxes, toy chests and food packaging. The number of edges, or sharp sides formed by the intersection of two faces, can be found using a mathematical formula called Euler's formula. Euler's formula states that V-E+F=2, or vertices minus edges plus faces equals two.
Things You'll Need
Write Euler's formula in your notebook using the following format: V-E+F=2.
Rewrite the formula so that "E," the unknown variable, is alone on one side of the equation. This can be done in two steps. First, move the "E" to the opposite side of the equation to make it a positive; write V+F=E+2 beneath the original equation. Next, move the "2" to the left side of the equation so that the "E" stands alone on the right. When the "2" is moved, it becomes a negative, and so the next line in your notebook should be written as V+F-2=E.
Input numbers for the variables that are known -- in this case, vertices and faces. For example, if the prism has eight vertices and six faces, the formula will be rewritten as 8+6-2=E.
Solve the equation. In this case, the equation will be rewritten as 12=E or E=12, meaning that the number of edges in a rectangular prism is 12.
Tips & Warnings
- Use Euler's formula to find the number of vertices, faces or edges on various three-dimensional solids.
- Photo Credit Hemera Technologies/Photos.com/Getty Images
How to Figure How Many Vertices a Shape Has
Vertices or a vertex is the technical term used in geometry for the corner points of a solid shape. A technical word...
The Differences Between Cubes & Rectangular Prisms
Rectangular prisms are six-sided polygons; three-dimensional shapes of which all sides meet at 90-degree angles, like a box. Cubes are a special...
Properties of Rectangular Prisms
A rectangular prism is a three-dimensional solid with several properties relating to its shape, volume and surface area. Rectangular prisms are one...
What Is the Length of a Rectangular Prism?
The length of a rectangular prism can be found in just a few quick moments of your time. Find out about the...
How to Find the Vertex of a Prism
Finding the vertex of a prism requires you to keep a few very important things in mind. Find out how to locate...
How Many Corners Does a Rectangular Prism Have?
The total number of corners that a rectangular prism has depends entirely on a few key things. Learn to tell how many...
How Many Parallel Lines Are in a Rectangular Prism?
A rectangular prism, by definition, will have a certain amount of parallel lines. Find out how many parallel lines are in a...
How to Find the Base Edge Length of a Square Prism
Finding the base edge length of a square prism is a lot easier than you might think at first. Find the base...