document.write( "Question 765156: Every time I try to solve this equation I come up with no solution, but that answer is incorrect. Help please?
\n" ); document.write( "[(11-x^2)^1/2]-[2/(11-x^2)^1/2]=1
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Algebra.Com's Answer #465975 by rothauserc(4718)\"\" \"About 
You can put this solution on YOUR website!
[(11-x^2)^1/2]-[2/(11-x^2)^1/2]=1
\n" ); document.write( "let u = [(11-x^2)^1/2] and then we have
\n" ); document.write( "u^2 -2 = u and
\n" ); document.write( "u^2 -u -2 = 0, factor this
\n" ); document.write( "(u-2) * (u+1) = 0, so we have
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\n" ); document.write( "[(11-x^2)^1/2] = 2
\n" ); document.write( "square both sides
\n" ); document.write( "11 -x^2 = 4
\n" ); document.write( "multiply both sides of = by -1
\n" ); document.write( "x^2 -11 = -4
\n" ); document.write( "x^2 = 7
\n" ); document.write( "x = sqrt(7)
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\n" ); document.write( "[(11-x^2)^1/2] = -1
\n" ); document.write( "square both sides
\n" ); document.write( "11 -x^2 = 1
\n" ); document.write( "multiply both sides of = by -1
\n" ); document.write( "x^2 -11 = -1
\n" ); document.write( "x^2 = 10
\n" ); document.write( "x = sqrt(10)
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\n" ); document.write( "now we substitute back in original equation to check
\n" ); document.write( "(11 -7)^1/2 - 2 / (11-7)^1/2 = 1
\n" ); document.write( "2 - (2 / 2) = 1
\n" ); document.write( "2 - 1 = 1
\n" ); document.write( "x = sqrt(7) checks out
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\n" ); document.write( "now for x = sqrt(10)
\n" ); document.write( "(11-10)^1/2 - 2 / (11-10)^1/2 = 1
\n" ); document.write( "1 -2/1 = -1
\n" ); document.write( "this does not check out
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\n" ); document.write( "our answer is x = sqrt(7) = 7^1/2
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