Problems 90–99. The purpose of these problems is to keep the material fresh in your mind so that you are better prepared for later sections, a final exam, or subsequent courses such as calculus.

Consider f (x) = −2x² − 10x + 3.

(a) Find the vertex.

(b) Is the parabola concave up or concave down?

(c) Find where f is increasing and where f is decreasing.