Answer:
Step-by-step explanation:
y = x^2 - x - 2 is a quadratic function. It's easily factorable: y = (x + 1)(x - 2). Setting this result equal to zero yields the x-intercepts: -1 and 2. This matches the x-intercepts shown on the graph.
The axis of symmetry, x = -b/(2a), derived from the coefficients 1, -1 and -2 of this particular function, is x = 1/2. This x = 1/2 is also the x-coordinate of the vertex. To find the y-coordinate of the vertex, we evaluate y = x^2 - x - 2 at x = 1/2, obtaining:
y = (1/2)^2 - (1/2) - 2, or y = 1/4 - 1/2 - 2, or -2 1/4. This does not quite agree with the y value (-2) shown in the diagram, but is close.
