
We eliminated both variables and arrived at a true statement.

Substitute y = 2x - 4 into the first equation:
#Solve using substitution how to
Now, we will see how to solve the following system of linear equations using the substitution method: Substitute y = -2 into the first equation: Substitute x = -1.5y + 2.5 into the second equation: Substitute y = 1.5 into the second equation: Substitute 4y - 2 for x into the first equation: Use the substitution method to solve the system of equations: In this section, we show you step by step how to solve several systems using the substitution method so that you can see how to do the substitution method in practice. Created by Sal Khan and Monterey Institute for Technology and Education.

This will allow you to solve for one variable, which you can then use to solve for the other. If the statement is true, then the system is dependent, i.e., it has infinitely many solutions. When solving a system of equations using substitution, you can isolate one variable and substitute it with an expression from another equation. If the statement is false, then the system is inconsistent, which means it has no solution. All you need to do is draw conclusions about the system depending on whether the statement you got is true (like 0 = 0 or 17 = 17) or false (e.g., 0 = 1 or 15 = 17): ⚠️ It may sometimes happen that you try to solve a system, and suddenly both variables vanish 😱 Keep calm! The variables are no more, but you arrived at some statements about numbers. If you want, you may test your solution: substitute the values you obtained into the system and see if everything is OK. That's it! You solved the system of equations by the substitution method. Substitute the value you got in Step 5 into one of the original equations. We have looked at how to solve equations with one unknown value, but what happens when there are two unknown values An equation with two unknown values will have infinitely many solutions. You have obtained a one-variable equation – solve it! This is the essence of solving systems by the substitution method!

In a nonlinear system, there may be more than one solution. Just as with systems of linear equations, a solution of a nonlinear system is an ordered pair that makes both equations true. Plug the result into the other equation (the one you didn't choose in Step 1). Definition 11.6.1 A system of nonlinear equations is a system where at least one of the equations is not linear. In the chosen equation, choose one of the variables. Now, let's discuss in detail how to do the substitution method: We have already explained what the substitution method is about and what the main idea behind it is.
