If the assumption is correct, then please use parenthesis. Saying x/(5-x) means you divide x all over (5-x) giving . The same applies for 7/(x-5) to indicate
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Factor -1 out of the expression 5-x to get -1(-5+x)
Rearrange -5+x into x-5
Simplify the first fraction. Note how the denominators are now both (x-5). This means we can combine the numerators over this common denominator.
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