For some reason I can't seem to edit my post, so I'll post this as an answer, just to give more info about my question.
We've only learned about the 3 basic formulas, these:
sin(x-y)=sin(x)cos(y)-cos(x)sin(y)
cos(x-y)=cos(x)cos(y)-sin(x)sin(y)
tan(x-y)=[tan(x)+tan(y)]/[1-tan(x)tan(y)].
(And their x+y counterparts)
Fairly certain I'm supposed to use these, with x-y=5 or x-y=10, x being one of the basic trigonometric numbers (0, 30, 45, 60, 90, 120, 135, 150, 180, 210, 225, 240, 270, 300, 315, 330, 360), and y=a+b or y=a-b in which both a and b are also one of those numbers. Is there a way to easily find out what x, a, and b would be, considering they have to be included in the basic trigonometric numbers?
Could be wrong about this entire theory, though.