Question

Evaluate g(n-5) if g(x)=x^2-6/2x

Answer 1

Answer: We want to evaluate g(x) in x = n -5, where g(x) = (x^2-6)/2x

then, doing it step by step: $g( n- 5)= \frac{(n-5)^{2} - 6 }{2*(n-5)}= \frac{(n^{2} - 2*5*n + 25) - 6 }{2n - 10} = \frac{n^{2} - 10n + 19 }{2n - 10}$

where i used that (a - b)^2 = a^2 -2ab + b^2

So the correct option is C.

Answer 2

G(x) = (x^2-6) / 2x 

g( n-5) = ( [n-5]^2 -6) / 2(n-5) 

= ( n^2 -10n +25 -6 ) / 2(n-5) or ( n^2 -10n +25 -6 ) / (2n-10) 
Your Answer 

I did foil first and got n^2-10n+25 
then did 25-6 to get 19. 
so n^2-10n+25 is on top.////// should have been n^2 -10n +19 
and the bottom is 2(n-5) so I distributed the 2 and got 2n-10 

so n^2-10n+25 
2n-10 
= (n^2 -10n +19) / 2(n-5)