Hello from MrBillDoesMath!
Answer:
( x^2 - 10x + 23 ) /23
Discussion:
if f(x) = x^2 - 2, then find ( f(x-5) - f(5) ) / x
f(x-5) = (x-5)^2 - 2 = x^2 -10x + 25 - 2 = x^2-10x+23
f(5) = 5^2 -2 = 25 -2 = 23
The ratio of these values is ( x^2 - 10x + 23 ) /23
Regards,
MrB