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X = - 4y -14x - 3y =91 solve by substitution

X = - 4y -14x - 3y =91 solve by substitution-example-1
User Delgan
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1 Answer

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We have a system of linear equations:


\begin{gathered} x=-4y-1 \\ 4x-3y=91 \end{gathered}

We have to solve it by substitution.

The first equation is giving us the equation to substitute x in the second equation and solve for y:


\begin{gathered} 4x-3y=91 \\ 4(-4y-1)-3y=91 \\ -16y-4-3y=91 \\ -19y=91+4 \\ -19y=95 \\ y=(95)/(-19) \\ y=-5 \end{gathered}

Now, we can use the first equation to solve for x:


\begin{gathered} x=-4y-1 \\ x=-4(-5)-1 \\ x=20-1 \\ x=19 \end{gathered}

Answer: x=19 and y=-5

User Kurt Stutsman
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