In a triangle ABC, D is the midpoint of BC. Join AD. Angle ADB = 45 degree and angle ACB = 30 degree. Find angle ABC.

(In reply to Solution by Bractals)

How did you jump from here: 

 2 cos(15)         1
   ----------- = ------------
      sin(?)      sin(135-?)

  to here:          or

    Angle ABC = ? = 105 degrees

?

Posted by Eric on 2006-02-25 14:41:04