document.write( "Question 414406: Which number is not real?
\n" ); document.write( "1.) -8
\n" ); document.write( "2.) sqrt(-64)
\n" ); document.write( "3.) - sqrt(64)
\n" ); document.write( "4.) 3 times sqrt(-64)\r
\n" ); document.write( "\n" ); document.write( "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! \n" ); document.write( "

Algebra.Com's Answer #290659 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
2) and 4) are not real because they both
\n" ); document.write( "have $\"sqrt%28-1%29\"$ in the expressions
\n" ); document.write( "----------
\n" ); document.write( "2)
\n" ); document.write( " $\"+sqrt%28-64%29+=+sqrt%2864%29%2Asqrt%28-1%29\"$
\n" ); document.write( " $\"sqrt%28-64%29+=+8i\"$
\n" ); document.write( "----------
\n" ); document.write( "4)
\n" ); document.write( " $\"3%2Asqrt%28-64%29+=+3%2A8%2Asqrt%28-1%29\"$
\n" ); document.write( " $\"3%2Asqrt%28-64%29+=+24i\"$ \n" ); document.write( "

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