Factor 16x2 + 289 by difference of squares?

Noor brought 21 sheets of stickers. she gave 1/3 of a sheet to each of the 45 students at recess. she wants to give teachers 1 1/2 sheets each.

Given f(x)= 9x+1 and g(x)=x^3, choose the expression (f*g)(x)

Which equation is y = -6x2 + 3x + 2 rewritten in vertex form?