Answer:
Length of the rectangle, L = 19 ft
Explanation:
Area of a rectangle = Length * Width
Area of the rectangle, A = 247 ft²
Let the length of the rectangle be L
The width of the rectangle = W
Since the width of the rectangle is 6 ft less that the length;
W = L - 6
A = L * W
247 = L * (L - 6)
247 = L² - 6L
L² - 6L - 247 = 0
By solving the quadratic equation above:
(L - 19)(L + 13) = 0
L - 19 = 0, L = 19
L + 13 = 0; L = -13
Since the length of a rectangle cannot be negative, L = 19 ft