A party-favor bag must have a volume of 140 cubic inches and the dimensions that are shown below. The equation x^3+6x^2-27x=140 can be used to find x.

height(x+9)in width(x-3)in length x in

What are the dimensions of the party-favor bag? Use a graphing calculator and a system of equations to find the answer.


The length is 7 inches, the width is 4 inches, and the height is 16 inches.

The length is 5 inches, the width is 2 inches, and the height is 14 inches.

The length is 4 inches, the width is 1 inch, and the height is 13 inches.

The length is 3 inches, the width is 0 inches, and the height is 12 inches.

Verified Answer :

The answer is:
B. 
The length is 5 inches, the width is 2 inches, and the height is 14 inches.
Hope this helps! :)

For this case we have the following equation for the volume:


\(x ^ 3 + 6x ^ 2-27x = 140
\)

Rewriting the equation we have:

\(x ^ 3 + 6x ^ 2-27x-140 = 0
\)

We factor the equation to find the roots of the polynomial.

We have then:

\((x-5) (x + 4) (x + 7) = 0
\)

Then, we discard the negative roots, because the dimensions of the figure must be positive.

We have then that the length is:


\(x = 5
\)

The height is:

\(x + 9 = 5 + 9 = 14
\)

The width is:


\(x-3 = 5-3 = 2
\)

Thus, the dimensions are:

\(5 * 14 * 2
\)

Answer:

The length is 5 inches, the width is 2 inches, and the height is 14 inches.