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Solve for X & y solve x + 4y = 0 when y = -2x + 7

User Ticex
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1 Answer

4 votes

Substitute -2x+7 for y in the equation x+4y=0 to obtain the value of x.


\begin{gathered} x+4(-2x+7)=0 \\ x-8x+28=0 \\ 7x=28 \\ x=(28)/(7) \\ =4 \end{gathered}

Substitute 4 for x in the equation y=-2x+7 to btan the value of y.


\begin{gathered} y=-2\cdot4+7 \\ =-8+7 \\ =-1 \end{gathered}

So answer is (4,-1).

User Maske
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