Solving a Systems of Equations by Elimination

To solve a system of equations by addition or subtraction (or elimination), you must eliminate one of the variables so that you could solve for one of the variables. First, in this equation, you must look for a way to eliminate a variable (line the equations up vertically and look to see if there are any numbers that are equal to each other). If there is lets say a –2y on the top equation and a –2y on the bottom equation you could subtract them and they would eliminate themselves by equaling zero. However, this equation does not have any equal terms. So instead we will multiply one or both equations by a number so that they will equal each other resulting in elimination. In this equation we will want to manipulate both equations so that the y’s will both equal –6 (I chose –6 because it is a common term among –2 and