Definition
A mathematical statement used to evaluate a value. An equation can use any combination of mathematical operations, including addition, subtraction, division, or multiplication. An equation can be already established due to the properties of numbers (2 + 2 = 4), or can be filled solely with variables which can be replaced with numerical values to get a resulting value. For example, the equation to calculate return on sales is: Net income ÷ Sales revenue = Return on Sales. When the values for net income and sales revenue are plugged into the equation, you are able to calculate the value of return on sales.
Use equation in a sentence

People in the business world are using more math to come up with the right equation to help out their bottom line.

In order to pass the first portion of the math class, which would determine whether or not you'd graduate, you had to know your way around an equation.

The teacher took each of the individual grades and placed into an equation to calculate each student's grade in the course.
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