SOLUTION: combine into a single fraction 5/x minus 7/(y+1) help please

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Question 1183337: combine into a single fraction
5/x minus 7/(y+1)
help please
Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
5%2Fx%22%22-%22%227%2F%28y%2B1%29

The LCD is the product of the two denominators, x(y+1)
So we multiply both fractions by %28x%28y%2B1%29%29%2F%28x%28y%2B1%29%29 which just 
equals 1 and thus will not change the value when we 
multiply both fractions by it:

expr%28%28x%28y%2B1%29%29%2F%28x%28y%2B1%29%29%29%2Aexpr%285%2Fx%29%22%22-%22%22expr%28%28x%28y%2B1%29%29%2F%28x%28y%2B1%29%29%29expr%287%2F%28y%2B1%29%29

Then we cancel away each original denominator, leaving
only the least common denominator in each:

expr%28%28cross%28x%29%28y%2B1%29%29%2F%28x%28y%2B1%29%29%29expr%285%2Fcross%28x%29%29%22%22-%22%22

Write as one fraction over the least common denominator

%285%28y%2B1%29-7x%29%2F%28x%28y%2B1%29%29

Remove the parentheses in the top. But not in the bottom
because the bottom is completely factored but the top is 
not.

%285y%2B5-7x%29%2F%28x%28y%2B1%29%29

Edwin