In an isosceles triangle ABC, AB = AC, XY || BC. If ∠A = 30°, the ∠BXY = ?

$$\eqalign{ & {\text{If }}\angle A = {30^ \circ } \cr & {\text{Then }}\angle ABC = \angle ACB = \frac{{{{180}^ \circ } - {{30}^ \circ }}}{2} = {75^ \circ } \cr & \angle BXY = {180^ \circ } - \angle ABC \cr & = {180^ \circ } - {75^ \circ } \cr & = {105^ \circ } \cr} $$