Question 852308
Hello, I'm unclear as to the actual proportion, but I'm assuming it's


{{{(n-6)/3n=(n-5)/(3n+1)}}}


If this is the case, first, you need to cross-multiply, which you did, and you'd get:


(n - 6)(3n + 1) = 3n(n - 5) ----->


{{{3n^2+n-18n-6=3n^2-15n}}} ----->


{{{3n^2-17n-6=3n^2-15n}}}


Next, get all of the n's and n^2's to one side, and the numbers to the other side.  When you do this, you will get:


{{{-2n=6}}}


Now, you can solve for n, by dividing both sides of the equation by -2:


{{{(-2n)/-2=6/-2}}} ----->


{{{n=-3}}}, which is your answer