9514 1404 393
Answer:
(d) 27.9 units
Explanation:
For repetitive calculations, I like to let a spreadsheet do the work. The attached shows the length of each segment and the sum of all three.
The perimeter is about 27.9 units.
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The distance formula tells you the length of each segment.
d = √((x2 -x1)^2 +(y2 -y1)^2)
The top line segment is ...
d = √((16 -3)^2 +(-2 -(-1))^2) = √(169 +1) = √170 ≈ 13.038 . . . units
The lengths of the others are computed similarly. The perimeter is the sum of all of the side lengths. Adding clockwise, we find ...
P = 13.038 +7.616 +7.211 = 27.865 . . . . . rounds to 27.9 units