Okay, suppose we are given a parabolic function in the form: y = a(x - h)^2 + k, where a ≠ 0 The vertex (for a parabola, this is the turning point) will be at (h,k). If a < 0 then the parabola will open downwards and the vertex will be at the maximum, but if 0 < a then the parabola opens upwards and the vertex will be at the minimum. The parabola we've been given may be written as: y = 1(x - 0)^2 + (-7) This means the vertex is at (0,-7) and the parabola opens upwards, so the minimum value is -7. Let's look at a graph of the function: The blue curve is the parabola, and the dots on the curve represent the 4 smallest values of the parabola when x is an integer. The horizontal lines represent the value of the parabola for those integral values of x, namely: y = -7 y = -6 y = -3 y = 2 Does that make sense?