Question 1103417
The way you spaced your parts of the expression:
<pre>3/n-7 - 5/n+1</pre> suggests you are given  3/(n-7)-5/(n+1) or as rendered should appear more like {{{3/(n-7)-5/(n+1)}}}.


Common Denominator will be {{{(n-7)(n+1)}}}.


{{{(3/(n-7))((n+1)/(n+1)) - (5/(n+1))((n-7)/(n-7))}}}


{{{(3n-3-(5n-35))/(n^2-6n-7)}}}
Not finished; but YOU can finish this.