SOLUTION: Which number is not real? 1.) -8 2.) sqrt(-64) 3.) - sqrt(64) 4.) 3 times sqrt(-64) I already eliminated -8 and - sqrt(64) beacause I know they are real, I just don't unders

Question 414406: Which number is not real?
1.) -8
2.) sqrt(-64)
3.) - sqrt(64)
4.) 3 times sqrt(-64)
I already eliminated -8 and - sqrt(64) beacause I know they are real, I just don't understand the other two. Please help, Thank you!
Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
2) and 4) are not real because they both
have in the expressions
----------
2)

----------
4)

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