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)=2x2+5x+3
  • The width function g(x)=x+1

The area can be expressed as: A=L×W where L is the length and W is the width.

We can rearrange this equation to solve for the length L: L=AW=f(x)g(x)

Substituting the given functions: L=f(x)g(x)=2x2+5x+3x+1

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

  1. Factor 2x2+5x+3: We look for two numbers that multiply to 2×3=6 and add to 5. These numbers are 2 and 3. We can rewrite: 2x2+2x+3x+3=2x(x+1)+3(x+1)=(2x+3)(x+1)

  2. Thus, we have: 2x2+5x+3=(2x+3)(x+1)

  3. Now substituting back into our expression for length: L=(2x+3)(x+1)x+1

  4. Cancel out x+1 (assuming x+10): 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)=Fill this with 2x+3