How Do You Solve Systems Of Three Linear Equations?
Linear systems are groups of equations with x and y variables. These variables correspond to the x-axis and y-axis on a graph. Some systems have three equations. These take a little more work, but are no harder to solve than systems with two equations. All linear systems can have their solutions graphed by using the solved x, y coordinates. Write down your system.This article will use the following system of equations:x+y=92x+4y=10x-2y=21 Solve the simplest equation for y. Some systems may have one equation already solved. For instance, you may have x=0, or y=-1. If this is the case, proceed to Step 3 without solving any of the other equations.The simplest equation in this case is x+y=9. Solving this for y yields y=9-x. Substitute your equation from Step 2 in place of the y variable in one of the remaining equations. You can use either equation. Choose the equation that will be easier to solve.Substitute y=9-x for y in x-2y=21.x-2(9-x)=21x-18+2x=213x-18=213x=39x=13 Substitute the value
