7000 is 6709 rounded to the nearest thousand
20x + 5y is the correct answer
The 7 miles and 24 miles make up two "legs" of a right triangle.
The third side (or hypotenuse) is the distance between the towns.
distance^2 = 7^2 + 24^2
distance^2 = 49 + 576
distance^2 = 625
distance = square root of 625 or 25
The wire is about 11.18 m long. This can be found using the Pythagorean theorem.