Question

Me. Erickson did the following problem. She noticed she made a big mistake! What mistake did Ms. Erickson make while solving the problem?

(6x^3+4x-10)+(-3x^2+2x+8)=3x^3+6x-3

Answer 1

Her mistakes are;

She added unlike terms
`6x^(3)` and
`-3x^(2)` and gave the answer
`3x^(3)`

She added -10 and 8 and gave the answer -3

Explanation:

let us try to find her mistake

We have two algebric expressions to add them

→
`6x^(3)+4x-10`

→
`-3x^(2)+2x+8`

We must add the like terms

The like terms are:

→ 4x and 2x, -10 and 8

→
`4x+2x=6x`

→
`-10+8=-2`

So Let us add the expression to find her mistakes

`(6x^(3)+4x-10)+(-3x^(2)+2x+8)=6x^(3)-3x^(2)+6x-2`

The correct answer is:
`6x^(3)-3x^(2)+6x-2`

By comparing our answer with her answer her mistakes are:

1. She added unlike terms
   `6x^(3)` and
   `-3x^(2)` and gave the answer
   `3x^(3)`
2. She added -10 and 8 and gave answer -3