I'm tutoring a 13 year-old boy, a middle school student.
He has almost no problem with elementary algebra: he just applies the rules and everything falls into place. However he does struggle with geometry, since straight applying rules isn't always enough. The more complex the problem, the less he's able to find a path to the solution.
I'll give an example. We encountered a problem like this one:
Where the goal is to find the area of the shaded region. He was able to find the area of circular sector and triangle, but he could not put the pieces together without my help.
I don't want to suggest a solving path every time, because I'd like to improve his ability of finding one on his own. So, here's my question: what should I do in order to improve his problem-solving skills, especially when he needs to use some creativity to reach the solution?