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Solve the system by substitution. x = -8y-x + y = 18 Submit Answer

User Tim Lepage
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We have a system of linear equations:


\begin{gathered} x=-8y \\ -x+y=18 \end{gathered}

We have to solve by substitution. This is the most appropiate method a s we already have one of the variables in function of the other.

Then, we can replace x in the second equation as:


\begin{gathered} -x+y=18 \\ -(-8y)+y=18 \\ 8y+y=18 \\ 9y=18 \\ y=(18)/(9) \\ y=2 \end{gathered}

With the value of y, we can calculate x from the first equation:


x=-8y=-8\cdot2=-16

Answer: x=-16 and y=2

User AtErik
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