Answer:
√61 ≈ 7.81
Explanation:
It appears that the polygon can be enclosed by a rectangle that is 12 units wide and 10 units high. The enclosing circle is the one that will circumscribe that rectange. Its radius is half the length of the diagonal, so is ...
(1/2)√(12² +10²) = 1/2√244 = √61
The smallest circle that will surround the polygon will have a radius of √61 ≈ 7.81 units.
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The Pythagorean theorem is used to find the length of the diagonal. It tells you the square of the diagonal is the sum of the squares of the sides of the rectangle. Our radius is half the diagonal, so is half the square root of the sum of the squares of the side lengths.