I don't understand this, may someone explain this too me thanks.

Enter the number of complex zeros for the polynomial function f(x) = x 4+ 5x² +6

The tuition costs, c, for a local community college are modeled by c(h) = 250 + 200h, where h represents the number of credit hours taken. the local state university has tuition costs, s, modeled by the function s(h) = 300 + 180h. how many credit hours will a student have to take for the two tuition costs to be equal? round the answer to the nearest tenth of an hour.

Asequence is defined recursively using the formula f(n + 1) =f(n) - 5. which sequence could be