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Solve the system of linear equations by substitution. y = -2x - 9 Equation 6x - 5y = -19 Equation 2

User Asanas
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1 Answer

27 votes
27 votes

Solving by substitution method.

We have 2 equations:


y=-2x-9

and


6x-5y=-19

If we substitute the first equation into the second one, we get


6x-5(-2x-9)=-19

which gives


\begin{gathered} 6x-5(-2x)-5(-9)=-19 \\ 6x+10x+45=-19 \\ 6x+45=-19 \\ 6x=-19-45 \\ 6x=-64 \\ x=-(64)/(6) \\ x=-10.666 \end{gathered}

Now, we can substitute this result into the first equation, then we get


y=-2(-10.66)-9

then, we have


\begin{gathered} y=21.33-9 \\ y=12.33 \end{gathered}

Therefore, the solution of the system is


\begin{gathered} x=-10.66 \\ \text{and} \\ y=12.33 \end{gathered}

User A Bot
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