Step-by-step explanation:
We are given the following details:
A square and a regular octagon have the same perimeter. However the sides are not given. Let us assign a variable to the sides of the octagon. One side of the octagon would be represented by letter x.
Note that it is a regular octagon which means all eight sides have the same length. Next we are told that one side of the square is 7 feet longer than one side of the octagon. This means one side of the square would be 7 + x. Note that a square too has all four sides with equal length.
Therefore we would hav e the following;

Next we are told the two figures have the same perimeter.
The perimeter of an octagon is;

For a square we have;

Note however that the length of the square in this instance is (7 + x), hence we can re-write this equation as;

Since the perimeters for both are equal, we can equate both equations and we'll have;

We can now solve for the variable x;


Combine like terms;


Divide both sides by 4;

This means the length of a side of the octagon is 7 feet, while the length of a side of the square is 14 feet (7 + 7).
ANSWER:
