How Do You Solve Systems Of Equations By Substitution?
One common type of problem in algebra is to find the intersection of two linear equations to find their solution. Of graphing, elimination, and substitution, substitution is the most reliable and versatile technique. This tutorial will show you how to solve a system of equations by substitution. Solve one equation for a single variable. This sounds hard, but is pretty easy. Let’s use the system of equations X + Y = 2 2X -Y = 4 as an example. I am going to solve the first equation for X to get X = 2 – Y. This expression shows that X is equivalent to 2-Y, and I can use this to plug it into the second equation. Plug the solved equation into the other equation. Here we plug in (2-Y) wherever we see an X in the bottom equation 2(2-Y) – Y = 4 4 – 2Y – Y = 4 -3Y = 0 Y = 0 Now we know what Y is! Plug your value into your solved equation from step one to find the other variable. X = 2-Y X = 2-0 X =2 So our solution for this system of equations is X=2, Y=0, or the coordinate (2,0) which is the i
