Answer: The angle C measures 120 degrees.
Explanation:
For a polygon of n side, the sum of internal angle, in degrees is given by:
S = (n - 2) x 180
Parallelogram
4 sides, so
S = ( 4 - 2) * 180 = 360
Two pair of equal angles
B and D measure 60
A and C measure x. so
2ₓ + 2 * 60 = 360
2× = 240
× = 240/2
× = 120
The angle C measures 120 degrees
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