document.write( "Question 195697: 7x^2-16x-28=0\r
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Algebra.Com's Answer #146762 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( "\"7x%5E2-16x-28=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=7\", \"b=-16\", and \"c=-28\"\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-%28-16%29+%2B-+sqrt%28+%28-16%29%5E2-4%287%29%28-28%29+%29%29%2F%282%287%29%29\" Plug in \"a=7\", \"b=-16\", and \"c=-28\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2816+%2B-+sqrt%28+%28-16%29%5E2-4%287%29%28-28%29+%29%29%2F%282%287%29%29\" Negate \"-16\" to get \"16\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2816+%2B-+sqrt%28+256-4%287%29%28-28%29+%29%29%2F%282%287%29%29\" Square \"-16\" to get \"256\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2816+%2B-+sqrt%28+256--784+%29%29%2F%282%287%29%29\" Multiply \"4%287%29%28-28%29\" to get \"-784\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2816+%2B-+sqrt%28+256%2B784+%29%29%2F%282%287%29%29\" Rewrite \"sqrt%28256--784%29\" as \"sqrt%28256%2B784%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2816+%2B-+sqrt%28+1040+%29%29%2F%282%287%29%29\" Add \"256\" to \"784\" to get \"1040\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2816+%2B-+sqrt%28+1040+%29%29%2F%2814%29\" Multiply \"2\" and \"7\" to get \"14\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2816+%2B-+4%2Asqrt%2865%29%29%2F%2814%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+=+%2816%2B4%2Asqrt%2865%29%29%2F%2814%29\" or \"x+=+%2816-4%2Asqrt%2865%29%29%2F%2814%29\" Break up the expression.\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%288%2B2%2Asqrt%2865%29%29%2F%287%29\" or \"x+=+%288-2%2Asqrt%2865%29%29%2F%287%29\" Reduce \r
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\n" ); document.write( "\n" ); document.write( "So the answers are \"x+=+%288%2B2%2Asqrt%2865%29%29%2F%287%29\" or \"x+=+%288-2%2Asqrt%2865%29%29%2F%287%29\" \r
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\n" ); document.write( "\n" ); document.write( "which approximate to \"x=3.446\" or \"x=-1.161\"\r
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\n" ); document.write( "\n" ); document.write( "# 2\r
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\n" ); document.write( "\n" ); document.write( "\"11x%5E2=8\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2=8%2F11\" Divide both sides by \"11\".\r
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\n" ); document.write( "\n" ); document.write( "\"x=%22%22%2B-sqrt%288%2F11%29\" Take the square root of both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"x=sqrt%288%2F11%29\" or \"x=-sqrt%288%2F11%29\" Break up the \"plus/minus\" to form two equations.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%282%2Asqrt%2822%29%29%2F11\" or \"x=-%282%2Asqrt%2822%29%29%2F11\" Simplify the square root.\r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=%282%2Asqrt%2822%29%29%2F11\" or \"x=-%282%2Asqrt%2822%29%29%2F11\".\r
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