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    • Thread Starter
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    I have a question to multiply 2 rationals to form one, but the answer i get seems to be wrong

    4/(x-2) and 6/(x+8)

    It says there is no need to multiply out the denominator so i get:

    24 / ((x-2)(x+8))

    How have i done this wrong?
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    It is not wrong.
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    (Original post by Carlo08)
    I have a question to multiply 2 rationals to form one, but the answer i get seems to be wrong

    4/(x-2) and 6/(x+8)

    It says there is no need to multiply out the denominator so i get:

    24 / ((x-2)(x+8))

    How have i done this wrong?
    That is clearly correct. What made you think it was wrong?
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    We get given weekly tests online (The idea is to get us to practice) and it keeps teling me it's wrong.
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    (Original post by Carlo08)
    We get given weekly tests online (The idea is to get us to practice) and it keeps teling me it's wrong.
    There is a mistake with this question on the test then.
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    The only other thing I can see that you might try is to FOIL the bottom to get a polynomial, but the work you have there is correct.
    • Thread Starter
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    Ok thanks for the help, the next one is talking about adding them, how do i find the lcd of the equations listed above?
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    The common denominator is (x-2)(x+8). Multiply each fraction by whatever part of this common denominator that fraction does not already have.
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    How do you mean?
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    \frac{4}{x-2}+\frac{6}{x-8}=\frac{4(x+8)}{(x-2)(x+8)}+\frac{6(x-2)}{(x-2)(x+8)}=\frac{4(x-2)+6(x+8)}{(x-2)(x+8)}

    edit: From there it's a matter of distributing what needs distributing, combining like terms, foiling what needs foiling, canceling things that can be canceled, and you have it.
 
 
 

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