Consider the triangle WZY and WXY,
[tex]\begin{gathered} WZ=WX\text{ (given)} \\ ZY=XY\text{ (given)} \\ WY=WY\text{ (common)} \end{gathered}[/tex]So the triangles WZY and WXY will be condruent by the SSS criteria.
Then the corresponding parts must be equal,
[tex]\angle ZWY=\angle XWY[/tex]Given that the angle ZWX measures 60 degrees,
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