Answer:
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Sum of interior angles of a regular polygon is:
- S = 180(n - 2), where n- sides of polygon
Find the measure of interior angle a:
- a = S/5 = 180(5 - 2)/5 = 540/5 = 108
Equate the values of angle a and solve for z:
- 3z + 72 = 108
- 3z = 108 - 72
- 3z = 36
- z = 12
Correct choice is B.