To solve this problem, we need to use the formulas for the perimeter and area of a circle and a square.
The perimeter of a circle is given by the formula: P = 2Ï€r, where P is the perimeter and r is the radius. In our case, since we are using x yards of fence for the circumference, we can set up an equation: P_circle = 2Ï€r = x.
The perimeter of a square is given by the formula: P = 4s, where P is the perimeter and s is the length of each side. Since we are using (1000 - x) yards of fence for the perimeter, we can set up an equation: P_square = 4s = 1000 - x.
To find the area of the circle, we use the formula: A_circle = πr^2, where A_circle is the area and r is the radius.
To find the area of the square, we use the formula: A_square = s^2, where A_square is the area and s is the length of each side.
We want to maximize the combined area of both regions, so we want to find the values of x and (1000 - x) that will maximize the sum of A_circle and A_square.
To do that, we need to express the area of the circle and the square in terms of x.
Since we know that the perimeter of the circle is x, we can solve for r using the formula: r = x / (2Ï€).
Now we can substitute this value of r into the area formula for the circle: A_circle = π(x / (2π))^2 = x^2 / (4π).
For the square, we know that the perimeter is (1000 - x), so we can solve for s using the formula: s = (1000 - x) / 4.
Now we can substitute this value of s into the area formula for the square: A_square = ((1000 - x) / 4)^2 = (1000 - x)^2 / 16.
To maximize the combined area, we need to find the values of x and (1000 - x) that will maximize the sum of A_circle and A_square.
Let's define A_total as the combined area: A_total = A_circle + A_square.
Now we can substitute the expressions for A_circle and A_square into the equation for A_total:
A_total = (x^2 / (4Ï€)) + ((1000 - x)^2 / 16).
To maximize A_total, we can take the derivative of A_total with respect to x, set it equal to 0, and solve for x:
d(A_total) / dx = (2x / (4Ï€)) - (2(1000 - x) / 16) = 0.
Simplifying this equation gives us: x / (4Ï€) - (1000 - x) / 8 = 0.
Multiplying through by 8Ï€ gives us: 2Ï€x - (1000 - x)Ï€ = 0.
Expanding and rearranging, we get: x = 250Ï€ / (Ï€ + 2).
Using this value of x, we can find the corresponding value of (1000 - x) and calculate the areas of the circle and square.
Finally, we compare the areas for different values of x to find the maximum combined area.