The length of a rectangle is 5 in. more than 3 times its width. The quadratic function f (x) = x (3x + 5) represents the area of the rectangle in terms of its width. What is a reasonable domain of the function?

A) real numbers

B) all real numbers less than 50

C) all real numbers less than zero

D) all real numbers greater than zero

Question

Mathematics

Trace Spence

29 January, 05:11

The length of a rectangle is 5 in. more than 3 times its width. The quadratic function f (x) = x (3x + 5) represents the area of the rectangle in terms of its width. What is a reasonable domain of the function?

A) real numbers

B) all real numbers less than 50

C) all real numbers less than zero

D) all real numbers greater than zero

+3

Answers (1)

Know the Answer?

Ralph Marsh · Answer 1

F (x) = x (3x+5)

or

f (x) = 3x²+5x

Here the domain in general is: - ∞
But the length of the rectangle cannot be negative, therefore the domain is all real numbers greater than zero.

Option D is correct.