Question

f(15)= - 45, meaning when the width of the rectangular area is ft, the area would be ft². this interpretation in the context of the problem. based on the observations above, it is clear that an appropriate domain for the function is

Explanation:

Step1: Identify input value

The input value for the function $f$ is the width of the rectangular area. Here, the width is given as 15 ft.

Step2: Identify function - output value

The function value $f(15)= - 45$. In the context of area, this means when the width is 15 ft, the area is - 45 $ft^{2}$. But in the real - world context of area of a rectangle, area cannot be negative. So this interpretation is not valid in the context of the problem.

Step3: Determine domain

Since area of a rectangle cannot be negative, and assuming the function represents area in terms of width, an appropriate domain for the function would be values of width that result in non - negative area values. Typically, for a rectangle, width must be non - negative in a real - world context, so a possible domain could be $x\geq0$ (where $x$ represents the width).

Answer:

When the width of the rectangular area is 15 ft, the area would be - 45 $ft^{2}$. This interpretation is not valid in the context of the problem. An appropriate domain for the function is $x\geq0$ (assuming $x$ is the width of the rectangle).