The area of a rectangular field is represented by the polynomial x3+x2−14x−24 . The length of the field is represented by the polynomial x−4 . Determine the expression that represents the width of the field.(1 point)

1 answer

To determine the width of the rectangular field represented by the polynomial area \( A(x) = x^3 + x^2 - 14x - 24 \) and length represented by \( L(x) = x - 4 \), we can find the width by dividing the area by the length:

\[ W(x) = \frac{A(x)}{L(x)} = \frac{x^3 + x^2 - 14x - 24}{x - 4} \]

To perform this polynomial division, we can use synthetic division or long division. Here, I will use polynomial long division.

  1. Set up the division:

    Divide \( x^3 \) by \( x \) to get \( x^2 \).

    Multiply \( x^2 \) by \( x - 4 \) to get \( x^3 - 4x^2 \).

    Subtract this from the original polynomial:

    \[ (x^3 + x^2 - 14x - 24) - (x^3 - 4x^2) = 5x^2 - 14x - 24 \]

  2. Continue dividing:

    Now divide \( 5x^2 \) by \( x \) to get \( 5x \).

    Multiply \( 5x \) by \( x - 4 \) to get \( 5x^2 - 20x \).

    Subtract this from the new polynomial:

    \[ (5x^2 - 14x - 24) - (5x^2 - 20x) = 6x - 24 \]

  3. Final step:

    Now divide \( 6x \) by \( x \) to get \( 6 \).

    Multiply \( 6 \) by \( x - 4 \) to get \( 6x - 24 \).

    Subtract this from the polynomial:

    \[ (6x - 24) - (6x - 24) = 0 \]

Now, putting it all together, we have:

\[ W(x) = x^2 + 5x + 6 \]

Thus, the expression that represents the width of the field is:

\[ \boxed{x^2 + 5x + 6} \]

This expression can also be factored if needed. It factors to \( (x + 2)(x + 3) \).