document.write( "Question 266445: Find the value or values of y in the quadratic equation y^2+4y+4=7 \n" ); document.write( "
Algebra.Com's Answer #195750 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"y%5E2%2B4y%2B4=7\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"y%5E2%2B4y%2B4-7=0\" Subtract 7 from both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"y%5E2%2B4y-3=0\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "Notice that the quadratic \"y%5E2%2B4y-3\" is in the form of \"Ay%5E2%2BBy%2BC\" where \"A=1\", \"B=4\", and \"C=-3\"\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for \"y\":\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%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( "\"y+=+%28-%284%29+%2B-+sqrt%28+%284%29%5E2-4%281%29%28-3%29+%29%29%2F%282%281%29%29\" Plug in \"A=1\", \"B=4\", and \"C=-3\"\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-4+%2B-+sqrt%28+16-4%281%29%28-3%29+%29%29%2F%282%281%29%29\" Square \"4\" to get \"16\". \r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-4+%2B-+sqrt%28+16--12+%29%29%2F%282%281%29%29\" Multiply \"4%281%29%28-3%29\" to get \"-12\"\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-4+%2B-+sqrt%28+16%2B12+%29%29%2F%282%281%29%29\" Rewrite \"sqrt%2816--12%29\" as \"sqrt%2816%2B12%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-4+%2B-+sqrt%28+28+%29%29%2F%282%281%29%29\" Add \"16\" to \"12\" to get \"28\"\r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-4+%2B-+sqrt%28+28+%29%29%2F%282%29\" Multiply \"2\" and \"1\" to get \"2\". \r
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\n" ); document.write( "\n" ); document.write( "\"y+=+%28-4+%2B-+2%2Asqrt%287%29%29%2F%282%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( "\"y+=+%28-4%29%2F%282%29+%2B-+%282%2Asqrt%287%29%29%2F%282%29\" Break up the fraction. \r
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\n" ); document.write( "\n" ); document.write( "\"y+=+-2+%2B-+sqrt%287%29\" Reduce. \r
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\n" ); document.write( "\n" ); document.write( "\"y+=+-2%2Bsqrt%287%29\" or \"y+=+-2-sqrt%287%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"y+=+-2%2Bsqrt%287%29\" or \"y+=+-2-sqrt%287%29\"
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