document.write( "Question 963997: Under root(x^2+4*x-21) +under root(x^2-x-6)=under root (6*x^2 -5*x-39)
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Algebra.Com's Answer #588936 by Fombitz(32388)\"\" \"About 
You can put this solution on YOUR website!
\"sqrt%28x%5E2%2B4x-21%29+%2Bsqrt%28x%5E2-x-6%29=sqrt%286x%5E2+-5x-39%29\"
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\n" ); document.write( "Factor out the \"sqrt%28x-3%29\" from all terms.
\n" ); document.write( "\"sqrt%28x%2B7%29+%2Bsqrt%28x%2B2%29=sqrt%286x%2B13%29\"
\n" ); document.write( "Square both sides,
\n" ); document.write( "\"%28x%2B7%29%2B2sqrt%28%28x%2B7%29%28x%2B2%29%29%2B%28x%2B2%29=6x%2B13\"
\n" ); document.write( "\"2x%2B9%2B2sqrt%28%28x%2B7%29%28x%2B2%29%29%2B%28x%2B2%29=6x%2B13\"
\n" ); document.write( "\"2sqrt%28%28x%2B7%29%28x%2B2%29%29=4x%2B4\"
\n" ); document.write( "\"2sqrt%28%28x%2B7%29%28x%2B2%29%29=4%28x%2B1%29\"
\n" ); document.write( "\"sqrt%28%28x%2B7%29%28x%2B2%29%29=2%28x%2B1%29\"
\n" ); document.write( "Square both sides,
\n" ); document.write( "\"%28x%2B7%29%28x%2B2%29=4%28x%5E2%2B2x%2B1%29\"
\n" ); document.write( "\"x%5E2%2B9x%2B14=4x%5E2%2B8x%2B4\"
\n" ); document.write( "\"3x%5E2%2B9x%2B14=4x%5E2%2B8x%2B4\"
\n" ); document.write( "\"3x%5E2-x-10=0\"
\n" ); document.write( "\"%28x-2%29%283x%2B5%29=0\"
\n" ); document.write( "Remember we factored out the \"sqrt%28x-3%29\" before so that's still part of the solution.
\n" ); document.write( "We only removed it so that the calculation wouldn't be messier.
\n" ); document.write( "\"sqrt%28x-3%29%28x-2%29%283x%2B5%29=0\"
\n" ); document.write( "Three possible solutions:
\n" ); document.write( "\"sqrt%28x-3%29=0\"
\n" ); document.write( "\"x-3=0\"
\n" ); document.write( "\"x=3\"
\n" ); document.write( "Verifying,
\n" ); document.write( "\"sqrt%283%5E2%2B4%283%29-21%29+%2Bsqrt%283%5E2-3-6%29=sqrt%286%283%29%5E2+-5%283%29-39%29\"
\n" ); document.write( "\"sqrt%289%2B12-21%29+%2Bsqrt%289-9%29=sqrt%2854+-15-39%29\"
\n" ); document.write( "\"0%2B0=0\"
\n" ); document.write( "True, good solution.
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\n" ); document.write( "\"x-2=0\"
\n" ); document.write( "\"x=2\"
\n" ); document.write( "Verifying,
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\n" ); document.write( "\"sqrt%284%2B8+-21%29+%2Bsqrt%284-2-6%29=sqrt%28+24-5%282%29-39%29\"
\n" ); document.write( "\"sqrt%28-9%29+%2Bsqrt%28-4%29=sqrt%28+-25%29\"
\n" ); document.write( "Leads to a negative square root so not a real solution.
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\n" ); document.write( "\"3x%2B5=0\"
\n" ); document.write( "\"3x=-5\"
\n" ); document.write( "\"x=+%28-5%2F3%29+\"
\n" ); document.write( "Verifying,
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\n" ); document.write( "\"sqrt%2825%2F9-20%2F3-21%29+%2Bsqrt%2825%2F9%2B5%2F3-6%29=sqrt%2850%2F3%2B25%2F3+-39%29\"
\n" ); document.write( "\"sqrt%28-224%2F9%29+%2Bsqrt%28-14%2F9%29=sqrt%28-14%29\"
\n" ); document.write( "Leads to a negative square root so not a real solution.
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\n" ); document.write( "Only one real solution, \"x=3\"
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