The Algebra 1 course, often taught in the 9th grade, covers Linear equations, inequalities, functions, and graphs; Systems of equations and inequalities; Extension of the concept of a …

Learn the basics of algebra—focused on common mathematical relationships, such as linear relationships.

Systems of equations overview Introduction to systems of equations Equivalent systems of equations and the elimination method Solving systems of equations with substitution

The elimination method is a technique for solving systems of linear equations. This article reviews the technique with examples and even gives you a chance to try the method yourself.

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Solve systems of equation with one-step elimination (e.g., x-values or y-values cancel each other out).

Sal uses simple elimination to figure out how many cupcakes are eaten by children and adults. Created by Sal Khan.

Practice recognizing effective strategies when using elimination to solve a system of equations.

So it's possible to just do one thing to one equation and not the other? That seems wrong somehow. Wouldn't that mess the whole thing up?

Every time you multiply or divide a term of an equation, you have to do the same to the other terms, and to the other side of the equation. In your example (6/3)x+2x=13, we would do the …