Final answer:
The length of the third side of the triangle is 4√7 feet, obtained by simplifying the radicals of the given sides and using the perimeter of the triangle to solve for the missing length.
Step-by-step explanation:
To find the length of the third side of a triangle with a perimeter of ∖16√7 feet when two sides measure √343 feet and √175 feet, we first simplify the radicals of the given side lengths and then use the perimeter to solve for the third side.
The square root of 343 is equal to √(7²7²7) = 7√7, and the square root of 175 is equal to √(7²5²5) = 5√7. Now we know the perimeter (P) of the triangle must equal the sum of its sides, so:
P = 16√7 = √343 + √175 + third side
16√7 = 7√7 + 5√7 + third side
Combine the like terms:
16√7 = (7+5)√7 + third side
16√7 = 12√7 + third side
Subtract 12√7 from both sides to isolate the third side:
Third side = 16√7 - 12√7
Third side = (16 - 12)√7
Third side = 4√7 feet
Therefore, the length of the third side is 4√7 feet in simplest radical form.