Question

How do you graph and state the max/min for `f(x) = -2x^2 + 9`?

Answer 1

To find the max/min use `(-b)/(2a)`

`=> 0/-4=0`

The quadratic is negative so it is `nn` shaped so it will have a maximum. It crosses the `y` axis at 9 so the max is (0,9)

Put the values x=-3, -2, -1, 1, 2, 3 into the equation to obtain the corresponding y values and plot them accordingly.

You should have a `nn` shaped parabola symmetrically drawn across the y axis with a max point at (0,9).