Well, looking at the expression, it has a -5 on the leading term, that means is not just a quadratic, but is a parabolic graph and because the coefficient of the leading term is negative, is upside-down, or opening downwards.
because it opens downwards, it looks like an arc, comes from the bottom up up up gets to a "maximum" or U-turn (vertex), then goes back down down down. So, where's the vertex anyway?
so, that's where the vertex is, and the maximum value for f(x), is the y-coordinate of course, or 9.
because it opens downwards, it looks like an arc, comes from the bottom up up up gets to a "maximum" or U-turn (vertex), then goes back down down down. So, where's the vertex anyway?
so, that's where the vertex is, and the maximum value for f(x), is the y-coordinate of course, or 9.