SOLUTION: simplify 3 Over a+2 - 2 over a-1 the answer was a-7 over(a+2) (a-1) i just didint understand this what was it asking me to do please show steps and what i should do.

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Question 835145: simplify
3 Over a+2 - 2 over a-1 the answer was a-7 over(a+2) (a-1) i just didint understand this what was it asking me to do please show steps and what i should do.

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
3 Over a+2 - 2 over a-1 the answer was a-7 over(a+2) (a-1)
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Enter it like this:
3/(a+2) - 2/(a-1) not with "over" "under" etc.
You can use 3 sets of braces { } to get
3%2F%28a%2B2%29+-+2%2F%28a-1%29
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3%2F%28a%2B2%29+-+2%2F%28a-1%29
To combine fractions, the denominators have to be the same. You need a "common denominator."
The product of the DENs always works. For this one, that's (a+2)*(a-1)
3%2F%28a%2B2%29+-+2%2F%28a-1%29
= 3%28a-1%29%2F%28%28a%2B2%29%2A%28a-1%29%29+-+2%28a%2B2%29%2F%28%28a%2B2%29%2A%28a-1%29%29
Now that the DENs are the same, you can combine the numerator terms.
= %283a-3%29%2F%28%28a%2B2%29%2A%28a-1%29%29+-+%282a-4%29%2F%28%28a%2B2%29%2A%28a-1%29%29
= %28a-7%29%2F%28%28a%2B2%29%2A%28a-1%29%29