Answer:
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Given:
- The perimeter of a triangle - 16√7 feet,
- Two of the sides - √343 feet and √175 feet.
First, convert the two side length as below:
- √343 = √(49*7) = 7√7,
- √175 = √(25*7) = 5√7.
Now find the third side:
- 17√7 - (7√7 + 5√7) =
- 17√7 - 12√7 =
- 5√7
Hence the third side is 5√7 feet.