I plugged it into Excel like this: =17500*SQRT(2)... so? Maybe I looked at the wrong cell? I just quick plugged it into to the sheet I was working on other stuff with. I get Casper's number this time. I remembered to put the parabola negative (-x), but I goofed when I put the vertex at -4100, hence why my original answer has a wrong sign for the intercept. Good catch. I should've caught it when I plugged the equation in here to check: http://webgraphing.com/graphing_basic.jsp, but it puts the x-axis on the bottom regardless of where your y-axis is, so I missed it.