Please help me with #5 i would really appreciate it! ITS DUE TODAY

Jeremy wants to determine the number of solutions for the equation below without actually solving the equation.

How many and of which kind of roots does the equation f(x)=x3−x2−x+1

Alocal hamburger shop sold a combined total of 601 hamburgers and cheeseburgers on friday. there were 51 more cheeseburgers sold than hamburgers. how many hamburgers were sold on friday? a local hamburger shop sold a combined total of hamburgers and cheeseburgers on friday. there were more cheeseburgers sold than hamburgers. how many hamburgers were sold on friday?