document.write( "Question 336178: x^2+7x=18 \n" ); document.write( "
Algebra.Com's Answer #241061 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B7x=18\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B7x-18=0\" Subtract 18 from both sides.\r
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\n" ); document.write( "\n" ); document.write( "Notice that the quadratic \"x%5E2%2B7x-18\" is in the form of \"Ax%5E2%2BBx%2BC\" where \"A=1\", \"B=7\", and \"C=-18\"\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-%287%29+%2B-+sqrt%28+%287%29%5E2-4%281%29%28-18%29+%29%29%2F%282%281%29%29\" Plug in \"A=1\", \"B=7\", and \"C=-18\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+sqrt%28+49-4%281%29%28-18%29+%29%29%2F%282%281%29%29\" Square \"7\" to get \"49\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+sqrt%28+49--72+%29%29%2F%282%281%29%29\" Multiply \"4%281%29%28-18%29\" to get \"-72\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+sqrt%28+49%2B72+%29%29%2F%282%281%29%29\" Rewrite \"sqrt%2849--72%29\" as \"sqrt%2849%2B72%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+sqrt%28+121+%29%29%2F%282%281%29%29\" Add \"49\" to \"72\" to get \"121\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+sqrt%28+121+%29%29%2F%282%29\" Multiply \"2\" and \"1\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+11%29%2F%282%29\" Take the square root of \"121\" to get \"11\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B+11%29%2F%282%29\" or \"x+=+%28-7+-+11%29%2F%282%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%284%29%2F%282%29\" or \"x+=++%28-18%29%2F%282%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+2\" or \"x+=+-9\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x+=+2\" or \"x+=+-9\" \r
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\n" ); document.write( "\n" ); document.write( "If you need more help, email me at jim_thompson5910@hotmail.com\r
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\n" ); document.write( "\n" ); document.write( "Also, feel free to check out my website. \r
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\n" ); document.write( "\n" ); document.write( "Jim
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