# Understand Systems of Equations

Videos and lessons to help High School students learn how to prove that, given a system of two equations in two variables, replacing one equation by the sum of that equation and a multiple of the other produces a system with the same solutions.

Common Core: HSA-REI.C.5

Related Topics:
Common Core (Algebra)

Common Core for Mathematics

Understanding systems of equations in two variables— Lesson 1 of 4 (Common Core Standard A-REI.5)
In this lesson you will learn what it means for a pair of numbers to be a solution to a system of linear equations by systematically testing values.

Understanding systems of equations in two variables— Lesson 2 of 4 (Common Core Standard A-REI.5)
In this lesson you will learn why multiplying an equation by a number does not change the solution to the system of equations by using the multiplication property of equality.

Understanding systems of equations in two variables— Lesson 3 of 4 (Common Core Standard A-REI.5)
In this lesson you will learn why adding two equations in a system of equations results in an equation with the same solution by using the addition property of equality.

Understanding systems of equations in two variables— Lesson 4 of 4 (Common Core Standard A-REI.5)

Understanding systems of equations example.

Understanding systems of equations example 2.

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You can use the free Mathway calculator and problem solver below to practice Algebra or other math topics. Try the given examples, or type in your own problem and check your answer with the step-by-step explanations.