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I want to see if I solved a problem correctly

I want to see if I solved a problem correctly-example-1
User Vlad Papko
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1 Answer

4 votes

The problem gives us two expressions:


\begin{gathered} y=9x-18 \\ y=18x \end{gathered}

And we need to solve for x. For that, the first step is to replace "y" on the first expression by the right side of the second expression:


18x=9x-18

Now we need to isolate the "x" variable on the left side:


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

We can now find "y" by replacing the value of "x" on the second expression:


y=18\cdot(-2)=-36

The value of x is equal to -2, and the value of y is equal to -36.

User Jonathan Wheeler
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