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Claudilovely
I have no clue how to do this with fractions, someone help and explain in words&numbers please! As stated: 4(3/4x-7)=4(1/2x+3) Thanks!
please use the draw tool and write this out
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sometimes it helps to make the other number a fraction to like this
you could even put a 1 under the seven|dw:1359405124046:dw|
Yeah, but how can you multiply the fractions? I tried to remember but I forgot. @moser90
|dw:1359405345652:dw| do you see what I did
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Oh! yeah, I get it! I get how you multiply the fractions, but then does that mean x will be a fraction? @mathstudent55
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yeah sorry I forgot the x so it would be 3x
The 4 outside each parentheses ends up canceling out with the 4 on the left and with the 1/2 on the right leaving a 2, that's why there are no fractions after the 4 is multiplied out. Remember that a number outside parentheses has to be distributed.
When you divide the numerator and denominator by the same number, you cross out. It's a way of simplifying the fraction. I can do it without crossing out. I'll show you.
|dw:1359405668580:dw| Now you can reduce the fraction 12/4 and the fraction 4/2 before going on.
|dw:1359405770394:dw| And I did this, is this correct?
12/4 = 3/1 = 3 4/2 = 2/1 = 1 So: |dw:1359405772980:dw|
You are allowed to add 3x to both sides, but in this case it won't help. Also, on the left side, 3x was positive, so you need to subtract 3x, not add 3x. But in the end, it's better to just subtract 2x from both sides, since you have 2x on the right side. By subtracting 2x, you move the x's to the left side. |dw:1359405951327:dw|
And finally: |dw:1359406000506:dw|
Oh my gosh, thank you!!
I never expected x to be so big. So when I plug the x to make it a 40 and do the "check" side of the problem, I multiply the same way with the fractions as before or do it differently? Like...
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how you make the 40 a ten and 40 a 20?
I simplify before multiplying. Look at the left side. There was a fraction of 3/4 multiplied by the number 40. You can write the number 40 as a fraction, 40/1, and multiply the fractions out: 3/4 * 40/1 = 120/40 Then you need to divide the numerator and denominator by the greatest common factor to reduce the fraction. In this case, the GCF is 40, so 120/40 = 30/1 = 30 What I did wass I reduced before multiplying. Since 40 is divisible by 4, and 4 is in the numerator and 4 is in the denominator, I divided 40 by 4, which is 10. Then when I multiplied 10 times 3 I got 30, which is the same 30 we got by multiplying everything out and reducing.
Ok, that makes sense.
On the right side, we had 1/2 times 40. 40 divided by 2 is 20, so you can divide the 40 by the 2 before multiplying by 1, and you get 20. Then you need to multiply by 1, but since multiplying by 1 does not change the number, 20 * 1 = 20.
Thank you for explaining that to me, before I thought I was looking at some kind of messed up nonsense.