Answer
Maximum area = 4900 m²
Step-by-step explanation
1.4.1 The perimeter of a rectangle is calculated as follows:
[tex]P=2(l+w)[/tex]where l is the length and w is the width of the rectangle.
Substituting P = 280 m, l = 2x meters, and w = y meters, and solving for y:
[tex]\begin{gathered} 280=2(2x+y) \\ \frac{280}{2}=\frac{2(2x+y)}{2} \\ 140=2x+y \\ 140-2x=2x+y-2x \\ 140-2x=y \end{gathered}[/tex]The area of a rectangle is calculated as follows:
[tex]A=l\cdot w[/tex]Substituting l = 2x and w = y = 140 - 2x:
[tex]\begin{gathered} A=2x(140-2x) \\ A=2x(140)-2x(2x) \\ A=280x-4x^2 \end{gathered}[/tex]1.4.2 Given that Area's formula is a quadratic function, its maximum is placed at its vertex. The x-coordinate of the vertex is found as follows:
[tex]x_V=\frac{-b}{2a}[/tex]where a is the leading coefficient and b is the x-coefficient of the function. In this case, the coefficients are a = -4 and b = 280, then:
[tex]\begin{gathered} x_V=\frac{-280}{2(-4)} \\ x_V=\frac{-280}{-8} \\ x_V=35 \end{gathered}[/tex]Evaluating the Area at x = 35, the maximum Area is:
[tex]\begin{gathered} A=280(35)-4(35)^2 \\ A=4900\text{ m}^2 \end{gathered}[/tex]