Final Answer:
The correct quadratic function expressing the rectangle's area in terms of its length is, given by A(l) = w(w + 5). Thus the correct option is B.
Step-by-step explanation:
In the provided options, we need to identify the quadratic function that represents the area of the rectangle in terms of its length. Let's analyze option B: A(l) = w(w + 5).
In this quadratic function, w represents the width and l represents the length of the rectangle. The problem statement states that the width is 5 feet less than the length. Therefore, we can express the width as l - 5 . Substituting this into the quadratic function, we get A(l) = (l - 5)(l - 5 + 5) = (l - 5)(l), which simplifies to A(l) = l(l - 5). This quadratic expression correctly represents the area of the rectangle in terms of its length.
Now, let's consider why the other options are incorrect:
- Option A ( A(l) = l(l) is a simple linear expression and does not account for the given condition that the width is 5 feet less than the length.
- Options C and D are incorrect because they involve unrelated constants (12) and do not correctly represent the relationship between the length and width.
In conclusion, option B (A(l) = w(w + 5)) is the accurate quadratic function that expresses the rectangle's area in terms of its length, considering the given information about the relationship between the length and width of the rectangle.