It should be all real numbers, because if you plug in lets say a 1 that would be 8(1-3) = 8(1) -24 or a 2 that would be 8(2-3)= 8(2) -24 8(-2) = 8 -24 8(-1) = 16 -24 -16 = -16 -8 = -8
We can use the vertex form of a quadratic, , to find that . Plugging ordered pairs into g(x), we see that a = 1. For example, for , . Solving for a gives 1.