A projectile is launched at an angle of 30 above horizontal, with a strong wind blowing horizontally. The path of the projectile is given by the parametric equations: X (90 cos 30)t2t2, y = (90 sin 30)t - 16t2 where x and y are the horizontal and vertical displacements from the launch point measured in feet. Find the slope of the tangent line to the projectile's motion at the instant it hits the ground (y = 0).