Elimination in mathematics refers to the elimination method, also called the addition method, which is used to solve basic algebraic problems by comparing two equations in order to find what their variables equal. This method uses two equations to cancel out a variable in one of the equations.
The elimination method works best when both of the equations have the same variables, so that there are no errors in the process along the way. Eliminating the extra numerals requires that both equations are compared together directly, and it is difficult to attain a simple whole number solutions from this if the two equations are vastly different. The two equations are also assumed to have the same values in their variables.
Another algebraic solving method is called the substitution method. This method requires manipulating the equations and keeping them balanced throughout the process. Looking at one of the equations, if one of them solves for one of the variables, you substitute that part for the variables in the other equation. For example, if x + y = 15, and x + 3 = y, you replace the y in the first equation, making the equation x + x + 3 = 15.