The polynomial x^3 + 5x^2 -57x -189 expresses the volume, in cubic inches, of a shipping box, and the width is (x+3) in. If the width of the box is 15 in., what are the other two dimensions? ( Hint: The height is greater than the depth.)

A.
height: 19 in.

depth: 5 in.

B.
height: 21 in.

depth: 5 in.

C.
height: 19 in.

depth: 7 in.

D.
height: 21 in.

depth: 7 in.

Question

The polynomial x^3  + 5x^2  -57x -189 expresses the volume, in cubic inches, of a shipping box, and the width is (x+3) in.  If the width of the box is 15 in., what are the other two dimensions? ( Hint: The height is greater than the depth.)

  A.
height: 19 in.

depth: 5 in.

  B.
height: 21 in.

depth: 5 in.

  C.
height: 19 in.

depth: 7 in.

  D.
height: 21 in.

depth: 7 in.

jdoe0001 · Answer

I assume you've done factoring of quadratics?

anonymous · Answer

Nope..but i havet cause idk what that is lol

jdoe0001 · Answer

well... you may want to ... cover that first I'd think

jdoe0001 · Answer

quadratic  ==   equation of 2nd degree

jdoe0001 · Answer

hint:   $\bf x^3  + 5x^2  -57x -189 \div (x+3)\to (ax^2+bx+c)\to (x+\square )(x+\square )$

anonymous · Answer

What are the value's of a,b and c? /.\

anonymous97 · Answer

i divided as he said and got x^2+2x-63

anonymous97 · Answer

so a=1 b=2 and c = -63

anonymous97 · Answer

idk what to do after that with his equation

jdoe0001 · Answer

as I said, you may want to cover your quadratics section first

anonymous97 · Answer

okay how do you do that?

anonymous · Answer

When you have the quadratic equation you can go about it by using the quadratic formula or by decomposing it by factoring the quadratic into two different values of X as jdoe0001 has shown above

anonymous · Answer

It requires the understanding of quadratics, show your work and someone will gladly guide you towards the proper solution. No better way to learn by than from your own mistakes.