Question

Find the sum and choose the correct answer.

2n 3 + 4n 2 - 7 and -n 3 + 8n - 9

-n3 - 4n2 - 8n - 16
n3 + 4n2 + 8n - 16
n3 + 4n2 + 8n + 16
3n3 + 4n2 + 8n - 2

Answer 1

@Abhisar

Answer 2

what do you think?

Answer 3

just combine like terms

Answer 4

A?

Answer 5

let's do the sum: \[\Large (2n^3 + 4n 2 - 7) + (-n^3 + 8n - 9)\]

Answer 6

We can see that \(2n^3\) and \(-n^3\) both have like term ( \(n^3\) ) so what's \(2n^3+(-n^3)\)?

Answer 7

im so confused gosh i hate math

Answer 8

try this...
like terms are gonna have the same letter and exponent

2n^3 - n^3 =
4n^2 -- no other like term
8n -- no other like term
-9 - 7 =

so what is 2n^3 - n^3......-n^3 is the same as -1n^3 if that helps.
and what is -9 - 7 ?

can you answer these 2 questions ?

Answer 9

no i dont like algebra im passing by a 60%

Answer 10

2n^3 - 1n^3.....the n^3 stays the same, so what is 2 - 1 ?

Answer 11

2-1=1

Answer 12

let me just show you...

2n^3 - n^3 = n^3
4n^2
8n
-9 - 7 = -16
now put it all together..
n^3 + 4n^2 + 8n - 16

please ask if you have any questions

Answer 13

2n^3 - n^3 is the same as 2n^3 - 1n^3 = 1n^3...which is the same as n^3