The area of a regular octagon is 35 cm2. What is the area of a regular octagon with sides five times as long?

A. 625 cm2

B. 875 cm2

C. 175 cm2

D. 245 cm2

The answer is B. 875 cm2. This is calculated by taking 35 * 5 * 5. The relationships between areas and side lengths of similar shapes is a squared relationship. Since the answer wanted 5 times, we do 5 times 5 and multiply that by our current area.