Answer:
x = 35
exterior angle measure = 82°
Explanation:
The angles denoted by (2x + 12) and (3x - 7) are a linear pair of angles formed at the vertex created by extending one side of the quadrilateral
Therefore they are supplementary angles whose sum = 180°
Therefore
2x + 12 + 3x - 7 = 180
2x + 3x + 12 - 7 = 180
5x + 5 = 180
Dividing by 5:
5x/5 + 5/5 = 180/5
x + 1 = 36
x = 36 - 1 = 35
The exterior angle is the one which has the expression 2x + 12
Plug in x = 35 to get
exterior angle measure = 2(35) + 12 = 70 + 12 = 82°