<h3>Answer:</h3><h3>Exact Surface Area =
</h3><h3>Approximate Surface Area = 535.425625842204</h3>
Round the approximate value however you need to
Units are in square centimeters.
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Work Shown:
You have the 160 portions correct since 20*8 = 160.
The other pieces are equilateral triangles, in which we use the formula
where x is the side length of the triangle. Plug in x = 8 to get
That's the exact area of one triangle, but we have two of them. Double the result to get
The total surface area is the sum of all the smaller areas
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The exact surface area is square cm.
Using a calculator, you should get
Round this however you need to.