check the picture below.
this is a case of the ambiguous case with an SSA, AC and CB are the sides and the angle is at A.
the ambiguous case has two triangles, the case when B is acute, CB sticks out, and the case when B is obtuse, CB sticks inside, it just so happen that those two angles for B are "supplementary" angles.
if you check the sin⁻¹ of that, we'll get the acute version of B, that's because of the constraints on the range of the inverse sine function, and we get ∡B ≈ 36.86989765°.
and of course, the other angle for B will be 180 - 36.86989765.