Andrew factored the expression 28x^3-42x^2+35x as 7x(4x^2+6x-5). But when Melissa applied the distributive law and multiplied out 7x(4x^2+6x-5) , she got 28x^3+42x^2-35x ; thus, Andrew’s solution does not appear to check. Why is that? Please help Andrew to understand this better. Explain your reasoning and correctly factor the original expression, if possible.

Can someone please help me with this question.

1 answer

Variations of this same questions have appeared many times in the last few days.
see "related questions" below

Andrew simply messed up, the correct factored answer is

7x(4x^2 - 6x + 5)