Step-by-step explanation:
If the zeros are 5 and 9, then the equation will have the form:
y = a (xβ5) (xβ9)
We know the point (0, 90) is on the curve, so we can use this to find the coefficient a:
90 = a (0β5) (0β9)
90 = 45a
a = 2
y = 2 (x β 5) (x β 9)