To find the measure of the exterior angle \( x \), we generally use the fact that the exterior angle of a polygon is equal to the sum of the two non-adjacent interior angles. However, in the case you've presented, it seems like you might just want to identify an exterior angle directly.
From what you've written, it’s unclear what other angles or information is involved. If you're asking if the exterior angle \( x \) could be one of the given options (37° or 42°), you would need more context or a specific figure.
If you have any specific triangle or polygon in context, please share that for a more precise answer!