Using X and Y to Represent the Axes
Date: 9/29/95 at 17:38:5 From: Fred Johnson Shane asks, "Why are the axes on a graph x and y and not any other letter in the alphabet?" Nate asks, "Why is the y-axis generally vertical and the x-axis generally horizontal?" Thanks for taking these questions, Fred Johnson
Date: 11/5/95 at 15:44:20 From: Doctor Rob Subject: Re: (no subject) Hi Fred, Nate and Shane. Both questions deal with mathematical conventions. No, not gatherings of mathematicians, but rules or practices that over time have developed in the mathematical community. In general, mathematicians use symbols from the end of the alphabet to signify variables and symbols from the beginning of the alphabet to signify constants. Similarly, in 2-variable situations x is usually the independent variable and y the dependent variable. There really is no reason for these conventions, and it's important to realize that you are free to use them or not when doing mathematics, as long as you define what represents what. Take care, and write back if you have any additional questions. -Doctor Rob, The Geometry Forum
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