Question

Janice completed the following polynomial addition. Find her error and correct her work.

Answer 1

B

Explanation:

Edge 2022

Answer 2

Option B.
`9x^(3)-2x^(2)-4x-2`

Explanation:

we have

`7x^(3)-2x^(2) +5`

`2x^(3)-4x-7`

Adds the polynomial

Group terms that contain the same variable

`(7x^(3)+2x^(3))-2x^(2)-4x+(5-7)`

Combine like terms

`9x^(3)-2x^(2)-4x-2`

Janice's error was

`-2x^(2) +5-4x-7=6x^(2)-12`

so

`-2x^(2)-4x=6x^(2)`

instead

`-2x^(2)-4x=-2x^(2)-4x`

and

`5-7=-12`

instead

`5-7=-2`