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  1. #1
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    help :)

    How do I do this
    A+3 over 8 + a over 5 = 2
    how do i solve and check it?
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  2. #2
    Super Member malaygoel's Avatar
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    Quote Originally Posted by happyboy
    How do I do this
    A+3 over 8 + a over 5 = 2
    how do i solve and check it?
    Take LCM and then cross multiply.

    Keep Smiling
    Malay
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  3. #3
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    A = 5 cross multiple the LHS so u get 5A + 15 + 8A all over 40 = 2 the rest is easy
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  4. #4
    MHF Contributor Quick's Avatar
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    Quote Originally Posted by happyboy
    How do I do this
    A+3 over 8 + a over 5 = 2
    how do i solve and check it?
    It's easier to understand if you see the work...

    $\displaystyle \frac{A+3}{8}+\frac{a}{5}=2 $ you need a common denominator

    $\displaystyle \frac{\left(A+3\right)\cdot5}{8\cdot5}+\frac{a \cdot 8}{5 \cdot 8}=2 $ Simplify

    $\displaystyle \frac{5A+15}{40}+\frac{8a}{40}=2 $ add the fractions..

    $\displaystyle \frac{5A+15+8a}{40}=2 $ Multiply both sides by 40

    $\displaystyle 5A+15+8a=2\cdot40 $ subtract 15 from both sides

    $\displaystyle 5A+8a=80-15 $ It's possible now to solve for both "A" and "a" but did you do a typo and they're really the same variable?

    $\displaystyle 5A+8a=80-15 $ assuming they are...add them together

    $\displaystyle 13A=65 $ and divide by 13

    $\displaystyle A=65\div13 $ and the answer is....

    $\displaystyle A=5 $
    Last edited by Quick; Jun 22nd 2006 at 05:04 AM.
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  5. #5
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    Quote Originally Posted by happyboy
    How do I do this
    A+3 over 8 + a over 5 = 2
    how do i solve and check it?
    You can mean,
    $\displaystyle \frac{\left( \frac{A+3}{8+A}\right)}{5}=2$
    or,
    $\displaystyle \frac{A+3}{\left( \frac{8+A}{5} \right)}=2$
    Which one is it, if any?
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