What two numbers multiply to 2 and add to -3 ?

What is the axis of symmetry of the function f(x)=-(x+ 9)(x-21)

Melanie is buying a bathing suit that costs 39.99. she is given a discount at the cash register of $6.00 when she scratched 15% off on a game piece for a store promotion. what will the sale price of melanie’s bathing suit be?

In which direction does the left side of the graph of this function point? a(x) = 3x - x2 + 4x - 2