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If u add the two equations 6x+4y=46 and -6x+9y=6 what do you get?

User IdahoB
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1 Answer

14 votes
14 votes

\begin{gathered} 6x+4y=46 \\ -6x+9y=6 \\ \Rightarrow0\cdot x+13y=52 \\ 13y=52 \\ y=(52)/(13) \\ y=4 \end{gathered}

Combining like terms


\begin{gathered} 6x+4y-6x+9y=46+6 \\ 6x-6x+4y+9y=46+6 \\ (6-6)x+(4+9)y=52 \\ 0\cdot x+13y=52 \\ 13y=52 \\ y=(52)/(13)=4 \end{gathered}

Think of y = 4 as y=f(x)=4

This means that for any value of x you replace, you will always get y = 4

User Nihulus
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