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

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)

In this lesson you will learn more about system of equations by adding a multiple of one equation to the another.

Understanding systems of equations example.

Understanding systems of equations example 2.

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