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# Subtracting algebra fraction help!! watch

1. Hi can someone please answer this question for me an explain the steps taken. Im working my way through k a strouds foundation book an he has a worked example but not explained and i cant get my head around it.

The question is
y+x/8x - y-x/4x

Alternatively

(y+x) (divided by) 8x - (y-x) (divided by) 4x
2. (Original post by Rjamesb)
Hi can someone please answer this question for me an explain the steps taken. Im working my way through k a strouds foundation book an he has a worked example but not explained and i cant get my head around it.

The question is
y+x/8x - y-x/4x

Alternatively

(y+x) (divided by) 8x - (y-x) (divided by) 4x
is it an expression or is there meant to be an answer?
3. (Original post by surina16)
is it an expression or is there meant to be an answer?
I think its simplfying
The final answer is
3/8 - y/8x
4. (Original post by Rjamesb)
I think its simplfying
The final answer is
3/8 - y/8x
okay :

1. to subtract fractions you need a common denominator.
the denominators are 8x and 4x, and although you would normally cross-multiply, it would be easier here to just multiply the second fraction by 2/2 so you get:
(y+x)/8x - (2y-2x)/8x
2. combining this into 1 fraction you get:
(y + x - 2y + 2x)/8x
It is +2x because you are subtracting a negative value
3. simplify the numerator:
(3x - y)/8x
I would leave it like this but your book takes it further so:
4. this is equivalent to:
3x/8x + -y/8x
The first fraction simplifies so you get:
3/8 - y/8x
5. (Original post by surina16)
okay :

1. to subtract fractions you need a common denominator.
the denominators are 8x and 4x, and although you would normally cross-multiply, it would be easier here to just multiply the second fraction by 2/2 so you get:
(y+x)/8x - (2y-2x)/8x
2. combining this into 1 fraction you get:
(y + x - 2y + 2x)/8x
It is +2x because you are subtracting a negative value
3. simplify the numerator:
(3x - y)/8x
I would leave it like this but your book takes it further so:
4. this is equivalent to:
3x/8x + -y/8x
The first fraction simplifies so you get:
3/8 - y/8x
Thanks alot for that, that was a great help
6. (Original post by Rjamesb)
Thanks alot for that, that was a great help
no problem! PM me anytime if you need help

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