Final answer:
The perimeter of the polygon is 30 units.
Step-by-step explanation:
To find the perimeter of the polygon with vertices at A(11,5), B(2,5), C(2,-1), and D(11,-1), we need to find the lengths of all the sides and add them together.
The length of AB is equal to the difference in x-coordinates, which is 11 - 2 = 9 units.
The length of BC is equal to the difference in y-coordinates, which is 5 - (-1) = 6 units.
The length of CD is equal to the difference in x-coordinates, which is 11 - 2 = 9 units.
The length of DA is equal to the difference in y-coordinates, which is 5 - (-1) = 6 units.
The perimeter of the polygon is then AB + BC + CD + DA = 9 + 6 + 9 + 6 = 30 units.
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