Question 150829: Hi, please answer this question.
I have: x^2-x-5=0. I know how to solve this using the quadratic equation method. The answers I get are (1+-sqrt(21))/2.
But instead of using the quadratic formula, can't I just say:
x=5 or x=6
How come this answer is different from the one using the quadratic formula???
Thank you. Answer by jim_thompson5910(28598) (Show Source):