X = 61 degrees.
Find the number of degrees in a pentagon by using the following formula:
(number of sides - 2)180 = 540.
There are 540 degrees in a pentagon.
Since we know four of the angles, we can subtract them from 540 to get the fifth angle.
540-138-144-107-90 = 61
Hope this helped =)
1B
2C
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