Respuesta :

 

hello :
the parabola's equation is : f(x) = a(x-5)²-5
the coefficient of the squared expression in the parabola's equation is : a
but ; f(6) = - 1
- 1 = a(6-5)²+5
a+5=-1.....a=-6
f(x) = -6(x-5)²+5

so : a = - 6

Answer:

-6

Step-by-step explanation: