/* Trajectory_ballistic  */
	/* launch velocity:  305 metres  */
	/* launch altitude:  1.3 metres  */
	/* launch angle:  5 degrees  */
	/* angle of a straight line:  constant 180 degrees  */
	/* acceleration of gravity:  constant 9.8 metres/second^2  */

SolveTime : solve(1.3+305*sin(5/180*%pi)*t-4.9*t^2 = 0, t)$
tMaxDist : subst(last(SolveTime),t)$   /* time to altitude 0  */
  MaxDistance : [305*cos(5/180*%pi)*tMaxDist, 1.3+305*sin(5/180*%pi)*tMaxDist-4.9*tMaxDist^2]$
tMaxHeight : 305*sin(5/180*%pi)/9.8$   /* time to maximum altitude  */
  MaxHeight : [305*cos(5/180*%pi)*tMaxHeight, 1.3+305*sin(5/180*%pi)*tMaxHeight-4.9*tMaxHeight^2]$

load('draw)$
draw2d(xlabel="distance (m)", ylabel="height (m)",
 yrange = [-.1*MaxHeight[2], MaxHeight[2]/.85], dimensions=[1024, 768],
 parametric(305*cos(5/180*%pi)*t, 1.3+305*sin(5/180*%pi)*t-4.9*t^2, t, 0, tMaxDist),

 color=red,
 label([sconcat(ev(round(MaxHeight[2]*100)/100, numer=true)), MaxHeight[1], MaxHeight[2]+2]),
 points([MaxHeight[1]],[MaxHeight[2]]),

 color=green,
 label([sconcat(ev(round(MaxDistance[1]*100)/100, numer=true)), MaxDistance[1], MaxDistance[2]-2]),
 points([MaxDistance[1]],[MaxDistance[2]])
);