Respuesta :

Answer:

y=-x^2-4x

Step-by-step explanation:

y=ax^2+bx+c

0=a(0)^2+b(0)+c

c=0

0=a(-4)^2+b(-4)+0

0=16a-4b

0=48a-12b

3=a(-3)^2-3b

0=9a-3b-3

0=36a-12b-12

48a-12b=36a-12b-12

12a=-12

a=-1

16a=4b

4a=b

b=4(-1)

b=-4

y=-x^2-4x

Hope this helps. I did it a longer way because sometimes the width varies, but for this one there is a zero at x=0 and x=-4 and the slope is negative so you can do y=-x(x+4)=-x^2-4x. Anyways... have a nice night.