Answer:
Perimeter = 72
Step-by-step explanation:
Notice that the adjacent (next to) lengths by each corner are equal in length.
This occurs when the quadrilateral is circumscribed.
Since 4.2 is adjacent to the length which makes up the total side 20.
20 – 4.2 = 15.8.
And 15.8 + 4.2 = 20.
(7 + 9) + (9 + 4.2) + (4.2 + 15.8) + (15.8 + 7) =
(16) + (13.2) + (20) + (22.8) =
(16 + 20) + (13.2 + 22.8) =
36 + 36 =
72
