Find (fºg)(2) and (f+g)(2) when f(x)= 1/x and g(x) = 4x +9

Which represents the solution set of the inequality 5x-9 < 21? a. x < 12/5 b. x > 12/5 c. x > 6 d. x < 6

How do i simply this expression (quadratic formula basis) on a ti-84 or normal calculator?

20.ju inces. which ordered pair is a viable solution if x represents the number of books he orders and y represents the total weight of the books, in ounces? (-3,-18) (-0.5, -3) (0,0) (0.5, 3)