Final answer:
The side length of each square plot in the flower garden is B) 6 feet.
Step-by-step explanation:
To solve this problem, we need to find the dimensions of each square plot in the flower garden. Let's assume the side length of each square plot is x feet.
The total area of the flower garden is the sum of the areas of the two squares and the border. The area of each square plot is x*x = x² square feet. The area of the border is (x+2)*(x+2) - x*x = 4x + 4 square feet. So, the total area is x² + x² + 4x + 4 = 2x² + 4x + 4 square feet.
Since the total area is given as 50 square feet, we can set up the equation: 2x² + 4x + 4 = 50. Simplifying this equation, we get: 2x² + 4x - 46 = 0.
Factoring the quadratic equation, we get: (x-6)(2x+8) = 0. Setting each factor equal to zero and solving for x, we find that x = 6 feet or x = -4 feet. Since the side length cannot be negative, the correct answer is x = 6 feet.