[v:15, a:45*%pi/180,g:9.18]$

[hx(t):=v*cos(a)*t,hy(t):=v*sin(a)*t-g/2*t^2];

wxplot2d([parametric,hx(t),hy(t),
[nticks,100],[t,0,2*%pi]],[x,-2,24.5],
[y,-1,10]);