Final answer:
To find the length of the diagonal piece of wood, we can use the Pythagorean theorem. In this case, the other two sides are the vertical boards. Therefore, the diagonal piece of wood should be approximately 113.25 inches long.
Step-by-step explanation:
To find the length of the diagonal piece of wood, we can use the Pythagorean theorem, which states that in a right triangle, the square of the length of the hypotenuse (diagonal) is equal to the sum of the squares of the other two sides. In this case, the other two sides are the vertical boards. Since each vertical board is 8 inches wide, and there are 12 vertical boards, the total width of the vertical boards is 8 inches x 12 = 96 inches.
So, we have a right triangle with one side measuring 96 inches and the other side measuring 5 feet (or 5 feet x 12 inches/foot = 60 inches). Let's use 'a' to represent the length of the diagonal piece (hypotenuse).
Using the Pythagorean theorem, we can write the equation:
a^2 = 96^2 + 60^2
a^2 = 9216 + 3600
a^2 = 12816
a = sqrt(12816)
a ≈ 113.25 inches
Therefore, the diagonal piece of wood should be approximately 113.25 inches long.