Related: How To Add a Target Line in Excel (Using Two Different Methods) When to add an equation to a graph in Excel In this article, we discuss scenarios when you may want to add an equation to a graph in Excel, describe why it's important to include supplemental information like equations, list a step-by-step guide for formatting your graph and equation on your own and provide several tips to help create your own graphs with equations using Microsoft Excel. Microsoft Excel is a program that gives users the opportunity to make tables, enter data, organize information and create graphs that correspond with specific equations. Graphs are a common visual aid in the worlds of business, finance and industries where progress and management are a critical part of achieving success.