Solving Systems of Linear Equations by Substitution Lesson

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In this section, we review solving systems of linear equations by substitution. Again we will look at systems with
two equations and two variables (x and y). When we solve a linear system in two variables, we are looking for any ordered pair that works
as a solution to each equation of the system. For the majority of systems, we are looking for one ordered pair. In special case scenarios,
there could be no solution or an infinite number of solutions. Here we will focus on an algebraic method known as substitution. Substitution
is more effective than graphing. It works for very large numbers, very small numbers, and non-integer values. Our method starts by solving
either equation for either variable. We then plug in for that variable in the other equation. This will yield a linear equation in one variable.
We can then solve that equation and find one of the unknowns of the system. Lastly, we plug in for the known value in either original equation.
This will allow us to find the other unknown. It is always good practice to check the result by plugging in the solution to both original equations.

Solving Systems of Linear Equations by Substitution Resources:

Videos:

Khan Academy - Video
Khan Academy - Video
Virtual Nerd - Video
Text Lessons:

Math Planet - Text Lesson
Purple Math - Text Lesson
Cliffs Notes - Text Lesson
Worksheets:

Math-Aids - Worksheet
Kuta - Worksheet
Khan Academy - Practice
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