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5x+8y=1024y=-15x-10Solve system by the elimination method

User Kingmakerking
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1 Answer

14 votes
14 votes

\begin{cases}5x+8y=10 \\ 24y=-15x-10\end{cases}

We need to solve the system above by elimination, which means we need to eliminate one of the variables. The first step is to change the "-15x" on the second equation from the right to the left as shown below:


\begin{cases}5x+8y=10 \\ 24y+15x=-10\end{cases}

We then need to multiply the first equation by -3.


\begin{gathered} \begin{cases}5x+8y=10\cdot(-3) \\ 24y+15x=-10\end{cases} \\ \begin{cases}-15x-24y=-30 \\ 24y+15x=-10\end{cases} \\ -15x+15x-24y+24y=-30-10 \\ 0=-40 \end{gathered}

Since the result is an invalid equation, the system is inconsistent and can't be solved.

User Jose Carrillo
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