Let angle ABC be called B and angle ACB be called C.
Let angle PBC be called B' and angle QCB be called C'.
B' < C' (B' is less than C') ----(1)
B' = 180 - B, C = 180 - C,
Substituting in (1),
180 - B < 180 - C
OR - B < - C
OR B > C (B is greater than C)
In a triangle, side opposite the greater angle is greater than the side opposite the smaller angle,
Hence side AC (opposite B, greater angel) > side AB (opposite C,smaller angle)