SOLUTION: I don't get this question at all please help me! How do you know that x^2 +9 is non-factorable over the set of real numbers? Thank you so much.

Algebra ->  Real-numbers -> SOLUTION: I don't get this question at all please help me! How do you know that x^2 +9 is non-factorable over the set of real numbers? Thank you so much.      Log On


   

Question 491159: I don't get this question at all please help me!


How do you know that x^2 +9 is non-factorable over the set of real numbers?

Thank you so much.
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
The sum of any two squares is NEVER factorable over the set of real numbers.


You can see if any quadratic is factorable by solving for x. If you get two real solutions, then you can factor it over the reals. But solving x^2+9 gives you x = 3i or x = -3i, which are not real.