I have designed a spring launcher for my class and it works really well using the range equation...x=sqrt(Rmg/KSin2(Theta)). So I have made a contraption that displaces the spring by x metres. I even have re-arranged and have it working using angles of launch and determining the range (R). Both work great. Here is my dilemma, I am having issues figuring out the proper angle (or displacement) to use when the spring does not land on the same level as the launch...i.e. either higher or lower in a target basket. I am having a hard time figuring out how to manipulate the equations to include the height. I have tried manipulating the equation from http://www.mwit.ac.th/~Physicslab/hbase/traj.html#tra8" [Broken] but to no avail. • x = how far you pull the spring back in meters • R = range: how far you want the spring to go in meters • m = mass of the spring in Kg • g = acceleration of gravity 9.8 m/s/s • K = spring constant in Newtons / meter • Theta = angle of launcher from horizontal If anyone can help me with this, it would be greatly appreciated.