9514 1404 393
Answer:
30°
Explanation:
Consecutive interior angles are supplementary when the lines are parallel:
2x +4x = 180°
x = 180°/6
x = 30°
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Comment on units
A lot of times the angles are assumed to be measured in degrees. Using that assumption, x=30 (degrees). When no units are specified, the angle measure defaults to radians. In radians, x = π/6. (We rarely see problems of this nature where the angles are expected to be measured in radians. More often, we see poorly edited questions where angles need to be assumed to be measured in degrees.)