Let WXYZ be a trapezoid with bases \overline{XY} and \overline{WZ}. In this trapezoid, $\angle ZXW = 120^\circ$, $\angle XWZ = 60^\circ$, and $\angle XYZ = 120^\circ$. Find $\angle YXZ$, in degrees.
I'm going to assume you meant angle YXW = 120 because otherwise, that wouldn't make sense Connect an altitude for X to WZ and call the point that intersects WZ, V. By similar triangles, we see that angle XZW is 30 degrees, and since XY and WZ are parallel (property of trapezoids), angle YXZ must be 30 degrees.