document.write( "Question 118200: I'm trying to solve the following equation:
\n" ); document.write( "The square root of [x+10] plus the square root of [x-6] equals 8.
\n" ); document.write( "I tried squaring both sides, and that eliminates some radicals, but it also creates some more!
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Algebra.Com's Answer #86301 by bucky(2189)\"\" \"About 
You can put this solution on YOUR website!
Given:
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\n" ); document.write( "\"sqrt%28x%2B10%29+%2B+sqrt%28x-6%29+=+8\"
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\n" ); document.write( "If you have two radicals involved, it often simplifies things to have one radical on one side
\n" ); document.write( "of the equal sign and the other radical on the other side. So let's begin by subtracting
\n" ); document.write( "\"sqrt%28x-6%29\" from both sides. When you do that the equation becomes:
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\n" ); document.write( "\"sqrt%28x+%2B+10%29+=+8+-+sqrt%28x-6%29\"
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\n" ); document.write( "Now square both sides. The left side becomes just x + 10. And on the right side you multiply:
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\n" ); document.write( "\"%288+-+sqrt%28x-6%29%29%2A%288+-+sqrt%28x+-+6%29%29\"
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\n" ); document.write( "Without going into the detail of multiplying these two binomials, the product is:
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\n" ); document.write( "\"64+-+16%2Asqrt%28x-6%29+%2B+%28x-6%29\"
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\n" ); document.write( "Substituting these new left and right sides into the equation results in:
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\n" ); document.write( "\"x%2B10+=+64+-+16%2Asqrt%28x-6%29+%2B+x+-6\"
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\n" ); document.write( "Subtract x from both sides of the equation ... which gets rid of the two x terms and leaves:
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\n" ); document.write( "\"10+=+64+-+16%2Asqrt%28x-6%29+-6\"
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\n" ); document.write( "On the right side combine the +64 and the -6 to make the right side become:
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\n" ); document.write( "\"10+=+-16%2Asqrt%28x+-+6%29+%2B+58\"
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\n" ); document.write( "Get rid of the 10 on the left side by subtracting 10 from both sides:
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\n" ); document.write( "\"0+=+-16%2Asqrt%28x-6%29+%2B+48\"
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\n" ); document.write( "Get rid of the radical on the right side by adding \"16%2Asqrt%28x-6%29\" to both sides and you
\n" ); document.write( "have:
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\n" ); document.write( "\"16%2Asqrt%28x-6%29+=+48\"
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\n" ); document.write( "Divide both sides by 16 and you reduce the equation to:
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\n" ); document.write( "\"sqrt%28x-6%29+=+3\"
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\n" ); document.write( "Square both sides to get:
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\n" ); document.write( "\"x+-+6+=+9\"
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\n" ); document.write( "Finally, solve for x by adding 6 to both sides to get rid of the -6 on the left side. When
\n" ); document.write( "you do that, you have the answer:
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\n" ); document.write( "\"x+=+15\"
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\n" ); document.write( "Check this answer by going back to the original equation:
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\n" ); document.write( "\"sqrt%28x%2B10%29+%2B+sqrt%28x-6%29+=+8\"
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\n" ); document.write( "Substitute 15 for x and it becomes:
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\n" ); document.write( "\"sqrt%2815%2B10%29+%2B+sqrt%2815-6%29+=+8\"
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\n" ); document.write( "and this reduces to:
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\n" ); document.write( "\"sqrt%2825%29+%2B+sqrt%289%29+=+8\"
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\n" ); document.write( "Taking the two square roots gives you:
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\n" ); document.write( "\"5+%2B+3+=+8\"
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\n" ); document.write( "That works ... so the answer of y = 15 looks good.
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\n" ); document.write( "Hope this helps you to understand the problem and how to solve it. Splitting the radicals ...
\n" ); document.write( "one on one side and the other on the other side seemed to help a bit.
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