document.write( "Question 156718: 2x^2+8x+15=0 \n" ); document.write( "
Algebra.Com's Answer #115547 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"2x%5E2%2B8x%2B15=0\" Start with the given equation.\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=2\", \"b=8\", 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-%288%29+%2B-+sqrt%28+%288%29%5E2-4%282%29%2815%29+%29%29%2F%282%282%29%29\" Plug in \"a=2\", \"b=8\", and \"c=15\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-8+%2B-+sqrt%28+64-4%282%29%2815%29+%29%29%2F%282%282%29%29\" Square \"8\" to get \"64\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-8+%2B-+sqrt%28+64-120+%29%29%2F%282%282%29%29\" Multiply \"4%282%29%2815%29\" to get \"120\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-8+%2B-+sqrt%28+-56+%29%29%2F%282%282%29%29\" Subtract \"120\" from \"64\" to get \"-56\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-8+%2B-+sqrt%28+-56+%29%29%2F%284%29\" Multiply \"2\" and \"2\" to get \"4\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-8+%2B-+2i%2Asqrt%2814%29%29%2F%284%29\" Simplify the square root (note: If you need help with simplifying square roots, check out this solver) \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-8%2B2i%2Asqrt%2814%29%29%2F%284%29\" or \"x+=+%28-8-2i%2Asqrt%2814%29%29%2F%284%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-4%2Bi%2Asqrt%2814%29%29%2F%282%29\" or \"x+=+%28-4-i%2Asqrt%2814%29%29%2F%282%29\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "So the answers are \"x+=+%28-4%2Bi%2Asqrt%2814%29%29%2F%282%29\" or \"x+=+%28-4-i%2Asqrt%2814%29%29%2F%282%29\" which are both complex (ie they are NOT real solutions)\r
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\n" ); document.write( "\n" ); document.write( "which approximate to \"x=-2%2B1.871%2Ai\" or \"x=-2%2B1.871%2Ai\"
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