ramp plotting in axes

Been trying to figure out how to make adjustable axes for adjustable ramps for a Projectile Motion simulation like this

%angle is alpha

alpha = input('input ramp degree: ')

Length=15

Jump_ramp = (Length*sind(alpha));

Land_Ramp = (pi* Jump_ramp);

plot([Jump_ramp,0],[Land_Ramp,0])

clearly the above is not working. Ive tried to use xlim but not show how or if that would even be correct to use

[Jan]

What exactly is the problem?

[Stephen23]

Duplicate:

https://www.mathworks.com/matlabcentral/answers/424421-ending-a-line-in-a-plot