Please Answer guys! :)

Francis is concerned some of the answers he put for his homework assignment are different than the answers his teacher gave to check with. After looking at his work, Francis is still pretty sure that he has the correct answer. What will his teacher tell him when Francis asks if he has simplified correctly

A.
“Francis, you distributed incorrectly.”
B.
“Francis, you multiplied monomials incorrectly after distributing.”
C.
“Francis, you didn’t combine like terms correctly.”
D.
“Good job, Francis! This is correct!”

Question

Please Answer guys! :)

Francis is concerned some of the answers he put for his homework assignment are different than the answers his teacher gave to check with. After looking at his work, Francis is still pretty sure that he has the correct answer. What will his teacher tell him when Francis asks if he has simplified correctly


A.
“Francis, you distributed incorrectly.”
B.
“Francis, you multiplied monomials incorrectly after distributing.”
C.
“Francis, you didn’t combine like terms correctly.”
D.
“Good job, Francis! This is correct!”

anonymous · Answer

his problem: 9x(x+3)-3(x^2+4x-5)+x

his work:  9x^2 +27x -3x^3 - 12x+15 + x

his answer:  6x^2 +15x +15

i know he got it wrong, correct answer is 6x^2 +16x+15 but i dont know where he messed up :)

anonymous · Answer

so i know its not b or d :)

anonymous · Answer

since you know the correct answer is $6x^2+16x+15$ and not $6x^2+\color{red}{15}x+15$ it appears that he did not combine the like terms correctly

anonymous · Answer

https://www.youtube.com/watch?v=9Pw5gUCJk5w