14)

The triangle has two equal sides, so it's an isosceles triangle. The angles opposite the equal sides are equal. Let the base angles be $$y$$. Then $$y + y + 88 = 180$$. $$2y = 92$$. $$y = 46$$. The angle $$x$$ is the vertex angle. $$x = 180 - 88 = 92$$.
Answer: $$x = 92$$.