As you seem to know yourself that’s what Reaction Manager is there for, and it’s really easy setting those kind of constraints with it, I just recreated what you are asking for in a matter of seconds with Reaction Manager, and I suggest you take a look at it’s documentation here, but for now follow these steps and maybe things will become more clear for you:
Press Alt+6 to launch Reaction Manager.
Press the green plus icon to add a master controller(In this case for instance the X_Position of an object)
*To add the controllers, after pressing the plus signs just hover over the objects and click again and select the controller.
3.Press the grey plus sign next to it to select the Slave(In this case for instance the Z_Rotation of the second object)
4.By default the first state is created for you in the States list(the second list), which corresponds to the initial state of both objects, so in this case we need a second state that corresponds to the second state of the Master(ie. the value of 20) and the second state of the Slave(ie. the value of 360).
5.To create the second(and consecutive) states in the States list, press the downward arrow next to the Create Mode button.
- Now in the ‘Values’ collumn of the list simply double-click the values and change the first one to 20, and the second one to 360, and that’s it.