Answer:
Around 173.8 km (rounded to the nearest tenth of a km
Explanation:
The area of an octagon can be found using the expression:
A=2(1+sqrt of 2)a^2
plug your side of 6 in to create the following equation:
A=2(1+sqrt of 2)(6^2)
Solve for A:
A= (2 + 2*sqrt of 2)(36) I multiplied 6 by 6 to get 36 and used distributive property on the other section.
A=72+72sqrt of 2
plug that in a calculator and you get around 173.8 km