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re-arrange the equation to make the speficied variable the subject watch

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    (5k − 7t)/11r = 9s, for t

    I tried doing this but got the answer wrong can someone please explain how to get to the answer which is t = (5k − 99rs)/7

    thanks
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    (Original post by lydiafoof)
    (5k − 7t)/11r = 9s, for t

    I tried doing this but got the answer wrong can someone please explain how to get to the answer which is t = (5k − 99rs)/7

    thanks
    (5k-7t) / 11r = 9s

    Start by multiplying both sides by (11r)
    (5k-7t) = 99rs

    then take away 5k from both sides
    -7t = 99rs - 5k

    next divide both sides by -7
    t = (99rs - 5k) / -7

    multiply the fraction by -1
    t = (-99rs + 5k) / 7

    and re-arrange to get it like the answer
    t = (5k-99rs) / 7
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    (Original post by Mr. Ee)
    (5k-7t) / 11r = 9s

    Start by multiplying both sides by (11r)
    (5k-7t) = 99rs

    then take away 5k from both sides
    -7t = 99rs - 5k

    next divide both sides by -7
    t = (99rs - 5k) / -7

    multiply the fraction by -1
    t = (-99rs + 5k) / 7

    and re-arrange to get it like the answer
    t = (5k-99rs) / 7
    Thank you, but why do I mutiply the fraction by -1?
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    (Original post by lydiafoof)
    Thank you, but why do I mutiply the fraction by -1?
    to move the minus sign from the bottom of the fraction to the top of the fraction (its actually multiplied by -1/-1), to put it in the form the question wants to
 
 
 
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