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how to solve y=3x-2 x-y=4You can solve the following equations by using elimination, substitution, graphing, and desmos.

User Skaffman
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1 Answer

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16 votes

Given the following System of equations:


\mleft\{\begin{aligned}y=3x-2 \\ x-y=4​\end{aligned}\mright.

Let's use the Substitution method to find the solution of this System of equations. You can follow these steps:

1. You must substitute the first equation into the second equation:


\begin{gathered} x-y=4​ \\ x-(3x-2)=4​ \end{gathered}

2. Now you must solve for "x":


\begin{gathered} x-3x+2=4 \\ -2x+2=4 \\ -2x=4-2 \\ x=(2)/(-2) \\ x=-1 \end{gathered}

3. To find the value of "y", you must substitute the value of "x" found above, into the first equation and then evaluate. This is:


\begin{gathered} y=3x-2 \\ y=3(-1)-2 \\ y=-3-2 \\ y=-5 \end{gathered}

Therefore, the solution is:


\begin{gathered} x=-1 \\ y=-5 \end{gathered}

User Casey Jordan
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