When is substitution better than elimination

An example:. Here it is easy to see that this system can be solved with the elimination method. This equation system might be a case where I would apply the substitution method, although I generally prefer the elimination method.

Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. Why use elimination method vs.

Ask Question. Asked 1 year, 6 months ago. Active 1 year, 6 months ago. Viewed 1k times. For an example of the substitution method see: Substitution method review systems of equations. Rodrigo de Azevedo CuriousIndeed CuriousIndeed 1 1 silver badge 9 9 bronze badges. Just to add a bit more information, "Elimination" Can have a variety of other interpretations. Elimination techniques typically refer to 'row reduction' to achieve 'row echelon form. They are used in Linear Algebra when referring to "Elimination techniques".

These techniques for elimination are preferred for 3rd order systems and higher. As the system of equations increases, the "condition" of a matrix becomes extremely important. Some of this may sound completely alien to you.

Don't worry about these topics until Linear Algebra when systems of linear equations Rank 'n' become larger than 2. Substitution is the preferred method for 2 equations in 2 unknowns. The constants are unimportant other than having a non-zero determinant. It is always easy to find multiplicative factors using LCMs of one variable or the other to allow substitution into the other equation:.

There are three ways to solve systems of linear equations: substitution, elimination, and graphing. Take the expression you got for the variable in step 1, and plug it substitute it using parentheses into the other equation. Use the result from step 3 and plug it into the equation from step 1. I create online courses to help you rock your math class. Read more. If necessary, rearrange both equations so that the??? If an equation appears to have not constant term, that means that the constant term is???

Multiply one or both equations by a constant that will allow either the??? Plug the result of step 4 into one of the original equations and solve for the other variable.

Graph both equations on the same Cartesian coordinate system. Find the point of intersection point of the lines the point where the lines cross.

Which method would you use to solve the following problem? Explain why you picked the method that you did. The easiest way to solve this system would be to use substitution since??? Whenever one equation is already solved for a variable, substitution will be the quickest and easiest method. To solve the system by elimination, what would be a useful first step? So we need to be able to add the equations, or subtract one from the other, and in doing so cancel either the???