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  1. #1
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    help

    can some one show me how to do this problem

    negative four times the sum of n and seven is equal to negative five times n minus nine
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  2. #2
    Grand Panjandrum
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    Quote Originally Posted by jim1174
    can some one show me how to do this problem

    negative four times the sum of n and seven is equal to negative five times n minus nine
    Translated into an equation this is:

    <br />
(-4)(n+7)=(-5)(n-9)<br />

    Multiply both sides of the equation by -1/4, and as
    a "-" times a "-" is a "+" this gives:

    <br />
n+7=(5/4)(n-9)<br />

    Now expand the brackets on the Right Hand Side of the equation:

    <br />
n+7=\frac{5}{4}n-\frac{45}{4}<br />

    Add 45/4 to both sides of the equation:

    <br />
n+\frac{73}{4}=\frac{5}{4}n<br />
.

    Subtract n from both sides:

    <br />
\frac{73}{4}=\frac{1}{4}n<br />
.

    Finlay multiply both sides by 4:

    <br />
73=n<br />
,

    so n=73

    RonL
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