In my native language, the word corresponding to the English verb motivate can be used to mean something like 'explain' or 'justify'. We could for instance ask someone to 'motivate' a particular point of view, a particular choice, a particular answer etc. When I check the various dictionaries I have access to it seems that motivate cannot be used in this sense in English, but when I google BrE web pages for "motivate your answer", I nevertheless get a number of hits that seem to support this use also in English – for instance:
Use the specific data given above to motivate your answer
If you wish, please motivate your answer (max. 1000 characters)
Describe the objective data you would collect from patient T and motivate your answer.
So, is it, after all, possible to use motivate in this sense in English, or are the above examples just bad English? If it is possible, would it also be possible to use a modified participle of this verb as a premodifier in a NP, as in well-motivated choices and well-motivated answers? If not, what could I use instead?