document.write( "Question 1001292: Which is the extraneous solution of -x = √2x+15?
\n" ); document.write( "The options are -5, -3, 3, or 5.\r
\n" ); document.write( "\n" ); document.write( "Extraneous solutions are very hard for me to find. Thank you for any help! \n" ); document.write( "
Algebra.Com's Answer #618532 by rothauserc(4718)\"\" \"About 
You can put this solution on YOUR website!
-x = sqrt(2x + 15)
\n" ); document.write( "square both sides of =
\n" ); document.write( "x^2 = 2x + 15
\n" ); document.write( "x^2 -2x -15 = 0
\n" ); document.write( "(x-5)*(x+3) = 0
\n" ); document.write( "x = 5 or -3
\n" ); document.write( "check answers
\n" ); document.write( "-(-3) = sqrt(9)
\n" ); document.write( "3 = 3
\n" ); document.write( "-5 = sqrt(25)
\n" ); document.write( "-5 = 5
\n" ); document.write( "*************************************************************************
\n" ); document.write( "-5 is the extraneous root
\n" ); document.write( "*************************************************************************
\n" ); document.write( "here is the graph of both equations, -x is red and sqrt(2x+15) is green
\n" ); document.write( "\"+graph%28+300%2C+200%2C+-10%2C+2%2C+-2%2C+10%2C+-x%2C+sqrt%282x%2B15%29%29+\"
\n" ); document.write( "solution is the intersection of the equations, therefore
\n" ); document.write( "x = -3\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "
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