Finding the Vertex

What is the vertex of the quadratic function f (-x) = (x - 3) (x - 2) ?

The vertex is - 0.25

Explanation: I have a Casio fx-9750Gll. I pressed menu and clicked on graph. i then typed in the equation and pressed EXE (which is enter). then, i pressed f5 (G-Solv) and that gives you two options, Max or Min. you can look at the graph to determine which one it is. but i pressed f3 (V-Window) which was the option Min and it gave me (2.5,-0.25) so the answer is - 0.25