Postby **Honeysuckle588** » Sat Jul 18, 2009 7:09 pm

I oriented my triangles with the side *b* along the horizontal (the initial side of angle A), and the side *c* as the terminal side. Then, drop a perpendicular line from the end of *c* down to the line that *b* sits on. It shouldn't take long for you to determine that the length of this vertical line is *c*sin(A).

One of the fun things about proofs is knowing what you are allowed to assume and use. If you are allowed to use the well-known fact that the area of a triangle is 0.5*(base)*height) then you're essentially done.

If you can't use that as a known fact, then there is a little more work to do.