In the diagram, hexagon has interior right angles at , , , , and and an exterior right angle at .
Also, , , and . The perimeter of is closest to
, 2022
Pick one
Solution
Extend and to meet at point . [[IMAGE0]] Since quadrilateral has three right angles (at , and ), it must have a fourth right angle at . Thus, is a rectangle, which means that and . The perimeter of is which is the perimeter of quadrilateral of . But quadrilateral has four right angles, and so is a rectangle. Also, , so is a square, and so the perimeter of equals Finally, , which means that
is isosceles as well as being right-angled at . By the Pythagorean Theorem, $QX^2 + XS^2 =
QS^22 QX^2 = 8^2QX^2 = 32QX>0QX = 2} =
Thus, the perimeter of is $40 + 4 = 40 + 62.6. (We could have left this as
40 + 62.6$.)
Of the given choices, this is closest to 63.
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