The area of a desktop in the shape of a rectangle is given by the function f(x)=2x2+5x+3

. The width of the desktop is given by the function g(x)=x+1
. What function represents the length of the desktop?

Enter the missing values.

(1 point)
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Remaining Attempts : 3

1 answer

To determine the length of the desktop, we can use the relationship that the area \( A \) of a rectangle is equal to the product of its length \( L \) and width \( W \).

In this case, we are given:

  • The area function \( f(x) = 2x^2 + 5x + 3 \)
  • The width function \( g(x) = x + 1 \)

The area can be expressed as: \[ A = L \times W \] where \( L \) is the length and \( W \) is the width.

We can rearrange this equation to solve for the length \( L \): \[ L = \frac{A}{W} = \frac{f(x)}{g(x)} \]

Substituting the given functions: \[ L = \frac{f(x)}{g(x)} = \frac{2x^2 + 5x + 3}{x + 1} \]

Now we need to simplify this expression. We can perform polynomial long division or factor if possible.

  1. Factor \( 2x^2 + 5x + 3 \): We look for two numbers that multiply to \( 2 \times 3 = 6 \) and add to \( 5 \). These numbers are \( 2 \) and \( 3 \). We can rewrite: \[ 2x^2 + 2x + 3x + 3 = 2x(x + 1) + 3(x + 1) = (2x + 3)(x + 1) \]

  2. Thus, we have: \[ 2x^2 + 5x + 3 = (2x + 3)(x + 1) \]

  3. Now substituting back into our expression for length: \[ L = \frac{(2x + 3)(x + 1)}{x + 1} \]

  4. Cancel out \( x + 1 \) (assuming \( x + 1 \neq 0 \)): \[ L = 2x + 3 \]

Therefore, the function that represents the length of the desktop is: \[ L(x) = 2x + 3 \]

Now, you can fill in the blank:

The function that represents the length of the desktop is: \[ L(x) = \text{Fill this with } 2x + 3 \]