But what happens when x=0 are we allowed to cancel?
This might arise on test day.
You cannot divide by zero. Hence if x = 0, you cannot cancel.
Former Senior Instructor, Manhattan GMAT and VeritasPrep
Vice President, Midtown NYC Investment Bank, Structured Finance IT
MFE, Haas School of Business, UC Berkeley, Class of 2005
MBA, Anderson School of Management, UCLA, Class of 1993