Question

The table shows the side length and approximate area of an octagonal stop sign.

Area of a Stop Sign

Which function can be used to compute the approximate area, in square inches, of a stop sign if it has a side length of x inches?
f(x) = 4.8x2
f(x) = 4x2
f(x) = (4.8)x

Answer 1

area = (# of sides * side length^2) / [4 * tan (180/n)]
area = (8 * x^2) / 4 * tan (22.5)
area = 8 x^2 / (4 * 0.41421)
area = 8 x^2 / 1.65684
area = 4.828 x^2

Answer 2

area = (# of sides * side length^2) / [4 * tan (180/n)]
area = (8 * x^2) / 4 * tan (22.5)
area = 8 x^2 / (4 * 0.41421)
area = 8 x^2 / 1.65684
area = 4.828 x^2

So, it seems the correct answer is the first one.