Question 923328
In a certain fraction, the denominator is 2 less than the numerator. 
d = n-2
If 1 is added to both the numerator and denominator, the resulting fraction is equal to 9/7. 
{{{((n+1))/((d+1))}}} = {{{9/7}}}
Find the original fraction.
Cross multiply
9(d+1) = 7(n+1)
9d + 9 = 7n + 7
9d = 7n + 7 - 9
9d = 7n - 2
replace d with (n-2)
9(n-2) = 7n - 2
9n - 18 = 7n - 2
9n - 7n = -2 + 18
2n = 16
n = 8
then obviously
d = 6
{{{8/6}}} is the original equation
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you can check this for yourself