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4 votes
Find the sum and choose the correct answer.

(2n 3 - 8n 2 + 7) + (n 3 + 8n - 9)

3n3 - 2
3n3 - 8n2 + 8n - 2
2n6 - 8n2 + 8n - 2
3n6 - n - 2

User Mike GH
by
7.7k points

1 Answer

4 votes
To put it in the simplest words :
Get rid of the parentheses and add like so:

2n^3 - 8n^2 + 7 + n^3 + 8n - 9
Combine like terms
2n^3+n^3= 3n^3
-8n^2 remains the same since there are no like terms for it
8n also remains the same
-9+7=-2
Put all of the numbers together
3n^3-8n^2+8n-2
Final answer:
B - the 2nd one
User Mathieu Seiler
by
8.1k points