Answer:
This value is exact. We can write this as 37.5*sqrt(3)
This approximates to roughly 64.9519
The units for the area are in square feet.
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Step-by-step explanation:
Split the regular hexagon into 6 identical equilateral triangles.
Each equilateral triangle has side length x = 5 ft.
The exact area of one of the equilateral triangles is
A = 0.25*sqrt(3)*x^2
A = 0.25*sqrt(3)*5^2
A = 0.25*sqrt(3)*25
A = 0.25*25*sqrt(3)
A = 6.25*sqrt(3)
Multiply this by 6 to get the exact area of the regular hexagon.
6*A = 6*6.25*sqrt(3) = 37.5*sqrt(3) which is the exact area in terms of radicals or square roots.
If your teacher meant to say choice B is 37.5*sqrt(3), then that would be the final answer. If your teacher only said 37.5 without the sqrt(3) term, then there's a typo.