document.write( "Question 169644: \"3x%5E2=-12x-1\" solve using the quadratic formula. I can do the first few steps. I am completely lost on the math involved between the last two steps. \n" ); document.write( "
Algebra.Com's Answer #125020 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"3x%5E2=-12x-1\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"3x%5E2%2B12x%2B1=0\" Add 12x to both sides. Add 1 to both sides.\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=3\", \"b=12\", and \"c=1\"\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-%2812%29+%2B-+sqrt%28+%2812%29%5E2-4%283%29%281%29+%29%29%2F%282%283%29%29\" Plug in \"a=3\", \"b=12\", and \"c=1\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-12+%2B-+sqrt%28+144-4%283%29%281%29+%29%29%2F%282%283%29%29\" Square \"12\" to get \"144\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-12+%2B-+sqrt%28+144-12+%29%29%2F%282%283%29%29\" Multiply \"4%283%29%281%29\" to get \"12\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-12+%2B-+sqrt%28+132+%29%29%2F%282%283%29%29\" Subtract \"12\" from \"144\" to get \"132\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-12+%2B-+sqrt%28+132+%29%29%2F%286%29\" Multiply \"2\" and \"3\" to get \"6\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-12+%2B-+2%2Asqrt%2833%29%29%2F%286%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+=+%28-12%2B2%2Asqrt%2833%29%29%2F%286%29\" or \"x+=+%28-12-2%2Asqrt%2833%29%29%2F%286%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "So the answers are \"x+=+%28-12%2B2%2Asqrt%2833%29%29%2F%286%29\" or \"x+=+%28-12-2%2Asqrt%2833%29%29%2F%286%29\" \r
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\n" ); document.write( "\n" ); document.write( "which approximate to \"x=-0.085\" or \"x=-3.915\"
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