Respuesta :

y = ax²+bx+c

Plug each pair in the above equation

for (3,0) → 0 = 9a +3b + c
for (-1,-12)→ -12= a - b + c
for (2, 3) → 3 = 4a +2b + c

Solving this system of 3 variables will give you:

a= -2
b= 7
c= -3

Then the quadratic equation becomes:

y = -2x² + 7x - 3