I'd like someone to double check a potential error in Official GMAT 12th Edition Review book.
page 123, section 5: Solving Equations by Factoring.
in the equation listed in this example problem, it appears to me that in the second step of factoring, the negative sign incorrectly turns into a positive sign within the left side of the equation. -2x squared turns into +2x squared. My calculations show that that it should remain -2x squared. Can someone double check this? I would appreciate it.
I hope someone will understand what I wrote above, I'm new to the forum and not sure yet how to write out equations on this message board.
You are correct. It is a typo, but it has been corrected in the step 3 again.