document.write( "Question 186671: solve, step by step √(x+5)+√(2x+3)=9\r
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\n" ); document.write( "( )=what is under the square roots
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Algebra.Com's Answer #139936 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"sqrt%28x%2B5%29%2Bsqrt%282x%2B3%29=9\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"sqrt%28x%2B5%29=9-sqrt%282x%2B3%29\" Subtract \"sqrt%282x%2B3%29\" from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B5=%289-sqrt%282x%2B3%29%29%5E2\" Square both sides\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B5=81-18%2Asqrt%282x%2B3%29%2B2x%2B3\" FOIL\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B5=84%2B2x-18%2Asqrt%282x%2B3%29\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"x%2B5-84-2x=-18%2Asqrt%282x%2B3%29\" Subtract 84 from both sides. Subtract 2x from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"-x-79=-18%2Asqrt%282x%2B3%29\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "\"%28-x-79%29%5E2=%28-18%2Asqrt%282x%2B3%29%29%5E2\" Square both sides\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B158x%2B6241=324%2A%282x%2B3%29\" FOIL and square the right side\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B158x%2B6241=648x%2B972\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B158x%2B6241-648x-972=0\" Get everything to the left side.\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-490x%2B5269=0\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "Notice we have a quadratic equation in the form of \"ax%5E2%2Bbx%2Bc\" where \"a=1\", \"b=-490\", and \"c=5269\"\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for x\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4ac+%29%29%2F%282a%29\" Start with the quadratic formula\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-%28-490%29+%2B-+sqrt%28+%28-490%29%5E2-4%281%29%285269%29+%29%29%2F%282%281%29%29\" Plug in \"a=1\", \"b=-490\", and \"c=5269\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28490+%2B-+sqrt%28+%28-490%29%5E2-4%281%29%285269%29+%29%29%2F%282%281%29%29\" Negate \"-490\" to get \"490\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28490+%2B-+sqrt%28+240100-4%281%29%285269%29+%29%29%2F%282%281%29%29\" Square \"-490\" to get \"240100\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28490+%2B-+sqrt%28+240100-21076+%29%29%2F%282%281%29%29\" Multiply \"4%281%29%285269%29\" to get \"21076\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28490+%2B-+sqrt%28+219024+%29%29%2F%282%281%29%29\" Subtract \"21076\" from \"240100\" to get \"219024\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28490+%2B-+sqrt%28+219024+%29%29%2F%282%29\" Multiply \"2\" and \"1\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28490+%2B-+468%29%2F%282%29\" Take the square root of \"219024\" to get \"468\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28490+%2B+468%29%2F%282%29\" or \"x+=+%28490+-+468%29%2F%282%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28958%29%2F%282%29\" or \"x+=++%2822%29%2F%282%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+479\" or \"x+=+11\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So the possible answers are \"x+=+479\" or \"x+=+11\"\r
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\n" ); document.write( "\n" ); document.write( "However, if you plug in \"x+=+479\", the original equation will NOT be true. So \"x+=+479\" is NOT a solution\r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So the solution is \"x+=+11\"
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