Question

What is a cubic polynomial function in standard form with zeros –4, –5, and 4

Answer 1

cubic means 3

having a zero of n is the equivalent of
x-n = 0
thus having zeros of -4,-5, and 4 is the equivalent of
x+4=0
x+5=0
x-4=0

hence
(x+4)(x+5)(x-4)=0 must be valid

now, finding the zero of an equation involves setting the y- coordinate point as 0, so working backwards

y=(x+4)(x+5)(x-4)

just expand the equation to get to standard form