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Hi I have a simple algebra question which i can work out like the following $\begin{align} x - 8 & = x/3 + 1/6 \\ 6(x - 8) & = 6(x/3 + 1/6) \\ 6x - 48 & = 6x/3 + 6/6 \\ 6x - 48 & = 2x + 1 \\ 6x & = 2x + 49 \\ 4x & = 49 \\ x & = 49/4 \end{align}$

However, if I were to first remove the $8$ from the right hand side: $\begin{align} x - 8 & = x/3 + 1/6 \\ x & = x/3 + 49/6 \\ 3x & = x + 49/6 \\ 2x & = 49/6 \\ \end{align}$ How do I go from $2x = 49/6$ to $x = 49/4$?

I'm pretty confused so any guidance would be appreciated.

1 Answers 1

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A correction is needed in the third step of your second argument: $3x=x +\color{red}3\cdot 49/6$.

That is from the second step: $ x={x\over3}+{49\over 6} $ you multiply both sides by 3 (and on the right, the "entire side"): $ 3\cdot x=3\cdot \bigl( {x\over3}+{49\over 6}\bigr) $to obtain $ 3x= 3\cdot{x\over3} +3\cdot{49\over 6} , $ or $ 3x= x + {49\over 2} ; $ which will give you the same solution as before, $x=49/4$.

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    Awesome, thanks alot.2012-04-24