document.write( "Question 602526: What is the solution set of the equation x^2+2x-15=0?\r
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Algebra.Com's Answer #380308 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"x%5E2%2B2x-15=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "Notice that the quadratic \"x%5E2%2B2x-15\" is in the form of \"Ax%5E2%2BBx%2BC\" where \"A=1\", \"B=2\", and \"C=-15\"\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-%282%29+%2B-+sqrt%28+%282%29%5E2-4%281%29%28-15%29+%29%29%2F%282%281%29%29\" Plug in \"A=1\", \"B=2\", and \"C=-15\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-2+%2B-+sqrt%28+4-4%281%29%28-15%29+%29%29%2F%282%281%29%29\" Square \"2\" to get \"4\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-2+%2B-+sqrt%28+4--60+%29%29%2F%282%281%29%29\" Multiply \"4%281%29%28-15%29\" to get \"-60\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-2+%2B-+sqrt%28+4%2B60+%29%29%2F%282%281%29%29\" Rewrite \"sqrt%284--60%29\" as \"sqrt%284%2B60%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-2+%2B-+sqrt%28+64+%29%29%2F%282%281%29%29\" Add \"4\" to \"60\" to get \"64\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-2+%2B-+sqrt%28+64+%29%29%2F%282%29\" Multiply \"2\" and \"1\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-2+%2B-+8%29%2F%282%29\" Take the square root of \"64\" to get \"8\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-2+%2B+8%29%2F%282%29\" or \"x+=+%28-2+-+8%29%2F%282%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%286%29%2F%282%29\" or \"x+=++%28-10%29%2F%282%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+3\" or \"x+=+-5\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x+=+3\" or \"x+=+-5\" \r
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\n" ); document.write( "\n" ); document.write( "This means that the solution set is {3,-5}\r
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\n" ); document.write( "\n" ); document.write( "Note: order of the solutions doesn't matter as you can also write the solution set as {-5,3}
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