A triangle T has vertices P, Q and R. The length of the edge between P and Q is 10,
and the angles at P and Q are 60degree and 45degree respectively. What is the radian measure
of the angle at R?
(A) 5pi/24 (B) 5/24 (C) 5pi/12 (D) 5/12 (E) None of the above.
60 + 45 + R = 180 Deg.
R = 75 Deg.
R = 75deg * (pi/180)rad/deg=5pi/12rad.