SOLUTION: What are the roots of the equation x^2+9=0 I got x=+-3i,can someone explain?

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Question 120476: What are the roots of the equation x^2+9=0 I got x=+-3i,can someone explain?
Answer by tutor_paul(519)   (Show Source): You can put this solution on YOUR website!

Get the x^2 term alone:

Take the square root of both sides:

Notice now you have to take the square root of a negative number of the right side. You can re-write this as:


Note that i is defined as follows:

So you can rewrite it as:

the square root of 9 is +/-3. So your final answer is:
x=+/-3i
==============
Good Luck,
tutor_paul@yahoo.com

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