Fill in the box with any number that will create a quadratic function with zeros at - 1 and 3.

3x^2 - __x-9

3x^2 - 6x - 9

Step-by-step explanation:

In order to make the function have zeros at - 1 and 3 it needs to factor into:

To make that:

3x^2 - 6x - 9

(3x - 9) (x + 1)

To check:

3x - 9 + 9 / 3 = 0 + 9 / 3

x = 3

x + 1 - 1 = 0 - 1

x = - 1

So, it is correct.

Answer: 3x^2 - 6x - 9