Compose the result function for 400 by replacing the function designators with the actual functions 400
5:8 is the ratio, pages:minutes. 5 is the amount of pages read, 8 is the minutes it took. 8 divided by 5 = 1.6 which would be the average time it took for him to read one page. A greater ratio would be anything higher than an average of 1.6 minutes per page.
6 what left? is "six" ok? if "six" instead of 6 letters is meant here, then you can:
the initial word is "Sixty"
You take "ty" away, you have six... which is 6!
A graph shows the function can be factored as
f(x) = (x -1)((x-8)² +1)
There is one real root and there are two complex roots. The latter can be found from the vertex form factor:
(x - 8)² + 1 = 0
(x - 8)² = -1
x - 8 = ±√(-1) = ±i
x = 8 ± i
The zeros of the function are {1, 8-i, 8+i}.