there are six different simple machines and multiple formulas. There is the pulley, the screw, the inclined plane, the wedge, the lever, and the wheel and axle. There are three different types of lever the first class lever were you have a fulcrum in the middle and then the load and the effort on opposite ends. There is the second class lever where there is the fulcrum and the load on one end and the effort on the other end. There is the third class lever where the load and the effort are on one end and the fulcrum on the other. The formula for inclined plane is IMA=length of incline/height of incline. The formula for mechanical advantage is MA= output force/input force. The lever formula is IMA= distance from input force to fulcrum/distance from output force to fulcrum. The formula for wheel and axle is IMA= radius of input/radius of output.