Answer:
y = 3/4( x+5)( x+4) ( x-1)
Step-by-step explanation:
The formula for the polynomial is
y = c( x- a1)( x- a2) ( x-a3) where c is a constant and a1,a2,a3 are the zeros
We have zeros -5,-4 and 1
y = c( x- -5)( x- -4) ( x-1)
y = c( x+5)( x+4) ( x-1)
We have a y intercept of -15
That means x=0 and y = -15
-15 = c ( 0+5)( 0+4) ( 0-1)
-15 = c( 5) ( 4) (-1)
-15 = c( -20)
Divide each side by -20
-15/-20 = c
3/4 =c
The equation is
y = 3/4( x+5)( x+4) ( x-1)
