document.write( "Question 199645: how do I solve these problems \r
\n" ); document.write( "\n" ); document.write( "1. 6x^2+7x=5\r
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\n" ); document.write( "\n" ); document.write( "2.12+5x-2x^2=0\r
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Algebra.Com's Answer #150058 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
# 1\r
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\n" ); document.write( "\n" ); document.write( "\"6x%5E2%2B7x=5\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"6x%5E2%2B7x-5=0\" Subtract 5 from both sides.\r
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\n" ); document.write( "\n" ); document.write( "Notice we have a quadratic in the form of \"Ax%5E2%2BBx%2BC\" where \"A=6\", \"B=7\", and \"C=-5\"\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%286%29%28-5%29+%29%29%2F%282%286%29%29\" Plug in \"A=6\", \"B=7\", and \"C=-5\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+sqrt%28+49-4%286%29%28-5%29+%29%29%2F%282%286%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--120+%29%29%2F%282%286%29%29\" Multiply \"4%286%29%28-5%29\" to get \"-120\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+sqrt%28+49%2B120+%29%29%2F%282%286%29%29\" Rewrite \"sqrt%2849--120%29\" as \"sqrt%2849%2B120%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+sqrt%28+169+%29%29%2F%282%286%29%29\" Add \"49\" to \"120\" to get \"169\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+sqrt%28+169+%29%29%2F%2812%29\" Multiply \"2\" and \"6\" to get \"12\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+13%29%2F%2812%29\" Take the square root of \"169\" to get \"13\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B+13%29%2F%2812%29\" or \"x+=+%28-7+-+13%29%2F%2812%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%286%29%2F%2812%29\" or \"x+=++%28-20%29%2F%2812%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+1%2F2\" or \"x+=+-5%2F3\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x+=+1%2F2\" or \"x+=+-5%2F3\" \r
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\n" ); document.write( "\n" ); document.write( "# 2\r
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\n" ); document.write( "\n" ); document.write( "\"12%2B5x-2x%5E2=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"-2x%5E2%2B5x%2B12=0\" Rearrange the terms.\r
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\n" ); document.write( "\n" ); document.write( "Notice we have a quadratic in the form of \"Ax%5E2%2BBx%2BC\" where \"A=-2\", \"B=5\", and \"C=12\"\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-%285%29+%2B-+sqrt%28+%285%29%5E2-4%28-2%29%2812%29+%29%29%2F%282%28-2%29%29\" Plug in \"A=-2\", \"B=5\", and \"C=12\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-5+%2B-+sqrt%28+25-4%28-2%29%2812%29+%29%29%2F%282%28-2%29%29\" Square \"5\" to get \"25\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-5+%2B-+sqrt%28+25--96+%29%29%2F%282%28-2%29%29\" Multiply \"4%28-2%29%2812%29\" to get \"-96\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-5+%2B-+sqrt%28+25%2B96+%29%29%2F%282%28-2%29%29\" Rewrite \"sqrt%2825--96%29\" as \"sqrt%2825%2B96%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-5+%2B-+sqrt%28+121+%29%29%2F%282%28-2%29%29\" Add \"25\" to \"96\" to get \"121\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-5+%2B-+sqrt%28+121+%29%29%2F%28-4%29\" Multiply \"2\" and \"-2\" to get \"-4\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-5+%2B-+11%29%2F%28-4%29\" Take the square root of \"121\" to get \"11\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-5+%2B+11%29%2F%28-4%29\" or \"x+=+%28-5+-+11%29%2F%28-4%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%286%29%2F%28-4%29\" or \"x+=++%28-16%29%2F%28-4%29\" Combine like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+-3%2F2\" or \"x+=+4\" Simplify. \r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x+=+-3%2F2\" or \"x+=+4\" \r
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\n" ); document.write( "\n" ); document.write( "# 3\r
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\n" ); document.write( "\n" ); document.write( "\"5x%5E2%2B16x-12=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "Notice we have a quadratic in the form of \"Ax%5E2%2BBx%2BC\" where \"A=5\", \"B=16\", and \"C=-12\"\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-%2816%29+%2B-+sqrt%28+%2816%29%5E2-4%285%29%28-12%29+%29%29%2F%282%285%29%29\" Plug in \"A=5\", \"B=16\", and \"C=-12\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-16+%2B-+sqrt%28+256-4%285%29%28-12%29+%29%29%2F%282%285%29%29\" Square \"16\" to get \"256\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-16+%2B-+sqrt%28+256--240+%29%29%2F%282%285%29%29\" Multiply \"4%285%29%28-12%29\" to get \"-240\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-16+%2B-+sqrt%28+256%2B240+%29%29%2F%282%285%29%29\" Rewrite \"sqrt%28256--240%29\" as \"sqrt%28256%2B240%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-16+%2B-+sqrt%28+496+%29%29%2F%282%285%29%29\" Add \"256\" to \"240\" to get \"496\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-16+%2B-+sqrt%28+496+%29%29%2F%2810%29\" Multiply \"2\" and \"5\" to get \"10\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-16+%2B-+4%2Asqrt%2831%29%29%2F%2810%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+=+%28-16%2B4%2Asqrt%2831%29%29%2F%2810%29\" or \"x+=+%28-16-4%2Asqrt%2831%29%29%2F%2810%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-8%2B2%2Asqrt%2831%29%29%2F%285%29\" or \"x+=+%28-8-2%2Asqrt%2831%29%29%2F%285%29\" Reduce. \r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x+=+%28-8%2B2%2Asqrt%2831%29%29%2F%285%29\" or \"x+=+%28-8-2%2Asqrt%2831%29%29%2F%285%29\"\r
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\n" ); document.write( "\n" ); document.write( "which approximate to \"x=0.627\" or \"x=-3.827\"
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