A gift bag is shaped like a rectangular prism and has a volume of 1152 cubic inches. The width of the bag is w, the length is 2w+4, and the height of the bag is 18-w (which is greater than the width). What are the dimensions of the bag?

Question

coconutjj · Answer

Solve:
(2w+4)(18-w)(w)=1152

anonymous · Answer

I got $$-2w ^{3}+32w ^{2}+72w$$

coconutjj · Answer

Yes...

anonymous · Answer

oh i have a question, do you keep the 1152 there or you subtract it and make it 0 on the other side?

coconutjj · Answer

Doesn't matter... but I would suggest you have the other side equal to zero, because I would assume you can solve this by factoring

anonymous · Answer

yeah that's what my algebra teacher is teaching factoring

anonymous · Answer

I got to that and I didn't know what to do next...

coconutjj · Answer

have u learned factor theorem?

anonymous · Answer

?

coconutjj · Answer

how did your teacher tell you to solve cubic equations

anonymous · Answer

factor it and then rewrite as frction and then cancel out / reduce

coconutjj · Answer

yes.. so how did he tell you to factor them

anonymous · Answer

find the GCF and then simplify it

coconutjj · Answer

Now how are you going to find the GCF ?

anonymous · Answer

by looking at what the #s are into

coconutjj · Answer

okkay... do you know how to approach this question then?

anonymous · Answer

sorry i can't explain it well

anonymous · Answer

kind of but its really confusing for me

coconutjj · Answer

what's confusing?

anonymous · Answer

i'm not good at factoring and all that numbers and a;;

anonymous · Answer

so what do i do next after that step?

anonymous · Answer

i really need help and i have to wake up early tomorrow can yuo  help me please

coconutjj · Answer

all coefficients are divisible by -2, factor out the -2 first...

anonymous · Answer

i put -2w because they all have w and are into 2

coconutjj · Answer

Uhh... is the right side of the equation = 0?

anonymous · Answer

yess? ... ?

coconutjj · Answer

so how did you factor out w from 1152?

anonymous · Answer

ohhhhhh i think that's where i went wrong

anonymous · Answer

$$-2w( (w ^{2}+18w)(-2w+36)-576$$

anonymous · Answer

so so fat i have that... what do i do next?

coconutjj · Answer

uhh... you mean$$-2(w^{3}-16w^{2}-36w+576)$$

anonymous · Answer

oh nevermind i forgot it was -2

anonymous · Answer

you can keep going now

coconutjj · Answer

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