Been working on this problem for 3 hours -- help

swampy

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Dec 16, 2008
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(7/4x - 1/12)(2/3x - 12/11) = 0
cannot seem to come up with fractions that will cancel each other out. Have always had problem understanding how to multiply fractions
(21/12x - 1/12) = 0
(22/33x - 36/33) = 0
how do I figure out the x

we are learning to solve equactions by factoring using the Principle of zero products .... but my instructor never did any fractions for an example. All I understand is the there are two different values for X ---
 

Subhotosh Khan

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swampy said:
(7/4x - 1/12)(2/3x - 12/11) = 0
What is it that you need to do? - solve for 'x'? simplify? what?

Please share with us your work, indicating where you are stuck - so that we know where to begin to help you.
 

Subhotosh Khan

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swampy said:
(7/4x - 1/12)(2/3x - 12/11) = 0
cannot seem to come up with fractions that will cancel each other out. Have always had problem understanding how to multiply fractions
(21/12x - 1/12) = 0 <<<< You did this correctly

\(\displaystyle \frac{21}{12}x \, = \, \frac{1}{12}\)

\(\displaystyle x \, = \, \frac{1}{12}\cdot \frac{12}{21}\)

\(\displaystyle x \, = \, \frac{1}{21}\)

similarly solve the next equation

(22/33x - 36/33) = 0
how do I figure out the x
 

mmm4444bot

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swampy said:
(21/12x - 1/12) = 0

(22/33x - 36/33) = 0

how do I figure out the x


It is more clear to put the grouping symbols around the fractional coefficient.

(21/12)x - 1/12 = 0

(22/33)x - 36/33 = 0

Solve each for x by first moving the constant to the right-hand side, followed by multiplying both sides by the reciprocal of the coefficient on x.

 

Denis

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swampy said:
(21/12x - 1/12) = 0
(22/33x - 36/33) = 0
Another way:
(21/12x - 1/12) = 0
Clearer if you write it this way:
21x / 12 - 1/12 = 0
(21x - 1) / 12 = 0
21x - 1 = 0
Finish it.
Do the other one similarly.
 
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