Algebra Math Question
A coordinate grid is placed on top of a drawing showing a wire that is hung between two poles. The tops of the poles lies on the x-axis. The wire is attached at the top of the poles. The function f(x) = 4x2 + 4x - 15 is used to model the vertical distance the wire hangs from the top of the poles. If x is the horizontal distance measured in yards, how far apart are the poles?