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Solve linear equations with unkowns on both sides. Including brackets and fractions.

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To solve an equation like

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$\\displaystyle{\\frac{\\var{a}}{y}=\\frac{\\var{b}}{y+\\var{c}}},$

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the first thing to deal with is that the unknown ($y$) that you are trying to find is in the denominator (on the bottom) of the fractions. In order to do that you first times by $y$ on both sides and $(y+\\var{c})$ on both sides leading to

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\\[\\var{a}(y+\\var{c}) = \\var{b}y.\\]

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From here, multiply out the brackets,

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\\[\\var{a}y +\\var{a*c} = \\var{b}y.\\]

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 Now collect the $y$-terms on one side and the numbers on the other,

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\\[\\var{a-b}y=\\var{-a*c}.\\]

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Finally divide by the coefficient of $y$,

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\\[y=\\frac{\\var{-a*c}}{\\var{a-b}}.\\]

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Use this link to find resources to help you revise how to solve linear equations

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Solve $\\displaystyle{\\frac{\\var{a}}{y}=\\frac{\\var{b}}{y+\\var{c}}}$.

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$y=$ [[0]] (Give your answer as a fraction)

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