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Promo Solving a system of equations by substitution

53 views · Published 23 July 2014 · 2:07 · Indexed 20 September 2026

Channel: Brian McLogan · 2014 · Education

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http://www.freemathvideos.com In this video playlist you will discuss how to solve a system of equations by substitution.  To do this we have to isolate one of the variables.  It is ideal to solve a system of equations when one of the variables is already isolated.  If not look to isolate the variable that has a coefficient of one or -1.  If that is still not the case look to determine which variable is easiest to solve for based on the coefficients being divisible into the constant.  Once you have solved for your variable you need to plug the expression that your variable equals in for the variable in the other equation.  Now you have one equation with one variable.  Combine like terms and solve for your variable.  Then take the value of your variable and plug it in for your variable in the other equation that is solved for the other equation.

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