Question

2x^2-x+3

Please explain how you factor this. I keep getting (2x - 3) (x + 1) and I'm not sure why I know the answer is (2x + 3) (x - 1) but I need to know what I did wrong

Answer 1

Did you copy the question wrongly? Should it be
`2x^2-x+3` or
`2x^2-x-3`? Because both answer (your answer and the textbook answer) did not give -3.

To check which is correct, we expand both answer back and see which one matches the question:

Your answer:

`(2x - 3)(x + 1) = 2x^2 + 2x - 3x - 3 = 2x^2 - x - 3`

textbook answer:

`(2x + 3)(x - 1) = 2x^2 - 2x + 3x - 3 = 2x^2 + x - 3`


So if the original question is
`2x^2-x-3` then your answer is correct and the textbook answer is wrong.

I hope this helps ....