Respuesta :

ghanami

Answer:

Step-by-step explanation:

hello :

f(x) = 10x²+20x-11     Completing The Square

f(x) = 10(x²+2x)-11 = 10((x²+2x+1)-1)-11

f(x) =10((x+1)²-1)-11

f(x)= 10(x+1)²-21...vertex form when the vertex is : (-1 ; -21)