Answer:
1/7 km long
Explanation:
The area of a square is any given one of the sides, squared. We can take this information and apply it to this problem. If the area is 1/49 km squared, we can take the square root of this to find the length of each side.
The square root of 1 is 1, and the square root of 49 is 7, so the answer is 1/7 km for each side.
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