Question

Which of these expressions CANNOT be simplified by combining like terms?

6fg3+4-4f2g2+f3g-12
6fg3+2f(2fg)+4f2g-10
6fg3+5f2g2+f3g-7
6f3g3+7f2g2+4f3g2-10fg

Answer 1

that would be : 6fg^3 + 5f^2g^2 + f^3g - 7....because there are no like terms

Answer 2

The answers are :

option 1,option 3 and option 4.

Explanation:

in first option:

`=6fg^3+4-4f^2g^2+f^3g-12`

clearly we could see that there are no like terms hence we could not simplify the expression.

in second option:

`=6fg^3+2f(2fg)+4f^2g-10`

this expression could also be written as:

`=6fg^3+4f^2g+4f^2g-10\\\\=6fg^3+8f^2g-10`

in third option:

`6fg^3+5f^2g^2+f^3g-7`

as there are no like terms hence the expression can't be simplified.

in fourth option:

`=6f^3g^3+7f^2g^2+4f^3g^2-10fg`

as there are no like terms hence the expression can't be simplified.

Hence option 1, option 3 and option 4 are the answers.