A parallelogram has one angle that measures 80 degrees. What are the measures of the three other angles in the parallelogram?

The opposite angle will be 80° as opposite angles and sides of a parallelogram are equal.

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The rest two angles will be 100° as adjacent angles are supplementary in a parallelogram.

The opposite angle is also 80°. since consecutive angles must total 180, the other 2 angles are 100 each. 100+100+80+80=360, as needed for a parallelogram