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Solve the following system using substitution -3x + 2y = 16 2x + y = 1

User Gehleh
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1 Answer

18 votes
18 votes

We have the system of equations:


\begin{gathered} -3x+2y=16 \\ 2x+y=1 \end{gathered}

We have to solve by substitution. We will clear y from the second equation and replace it in the first equation. Then solve for x:


\begin{gathered} 2x+y=1 \\ y=1-2x \end{gathered}
\begin{gathered} -3x+2y=16 \\ -3x+2(1-2x)=16 \\ -3x+2-4x=16 \\ -7x+2=16 \\ -7x=16-2 \\ -7x=14 \\ x=(14)/(-7) \\ x=-2 \end{gathered}

Now we can solve for y as:


y=1-2x=1-2(-2)=1-(-4)=1+4=5

Answer: x=-2 and y=5

User Rzassar
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