The range is the highest y value to the lowest y value
ok
find the vertex because it is the highest or lowest point in the equation make into f(t)=a(x-h)²+k form (h,k) is the vertex k is the y value of the vertex if a>0, then the vertex is the minimum if a<0, then the vertex is the maximum
so f(t)=t²-6t f(t)=t²-6t+9-9 f(t)=(t-3)²-9 f(t)=1(t-3)-9
k=-9 a=1 1>0 so y=-9 is the minimum value the maximum value will be infinity