SOLUTION: I need help with the following problem. I worked it out and got the wrong answer. multiply (15n-2) (2n^3 - 3n^2-4n-5) My answer was 30n^4 -49n^3 -54n^2 -67n + 10 The follow ar

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Question 297760: I need help with the following problem. I worked it out and got the wrong answer.
multiply (15n-2) (2n^3 - 3n^2-4n-5)
My answer was 30n^4 -49n^3 -54n^2 -67n + 10
The follow are the choices the answer could be according to my teacher.
10n4 - 19n3 - 14n2 - 17n + 10
10n4 - 19n3 - 26n2 - 33n - 7
10n4 - 15n3 - 20n2 - 25n + 10
4n3 - 6n2 + 8n + 10
I am not sure so any help with letting me know which is correct would be appreciated. Thank you

Found 3 solutions by user_dude2008, stanbon, richwmiller:
Answer by user_dude2008(1862)   (Show Source):
You can put this solution on YOUR website!
(15n-2) (2n^3 - 3n^2-4n-5)

15n(2n^3 - 3n^2-4n-5)-2(2n^3 - 3n^2-4n-5)

15n(2n^3) - 15n(3n^2)-15n(4n)-15n(5)-2(2n^3) +2(3n^2)+2(4n)+2(5)

30n^4 - 45n^3-60n^2-75n-4n^3 +6n^2+8n+10

30n^4 - 49n^3-54n^2-67n+10

Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website!
I like your answer.
Those others must be the answer to another problem.
Cheers,
Stan H.

Answer by richwmiller(17219)   (Show Source):
You can put this solution on YOUR website!
As you wrote the problem (15n-2)*(2n^3-3n^2-4n-5)
the multiplication produces
30n^4-49n^3-54n^2-67n+10
10 n^4-19n^3-14n^2-17n+10 comes from (5n-2)*(2n^3-3n^2-4n-5)
10n4 - 19n3 - 26n2 - 33n - 7 has no factors
10n4 - 15n3 - 20n2 - 25n + 10 has 5 as a factor
4n3 - 6n2 + 8n + 10 has 2 as a factor
You might double check whether it is 15n-2 or 5n-2
For those of you wondering, there was a typo. It should have been 5n-2.