document.write( "Question 99589: solve each equation for x\r
\n" ); document.write( "\n" ); document.write( "x^2 + 4x + 4 = 7
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Algebra.Com's Answer #72449 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"x%5E2+%2B+4x+%2B+4+=+7\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2+%2B+4x+-3+=+0\" Subtract 7 from both sides\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( "Starting with the general quadratic\r
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\n" ); document.write( "\n" ); document.write( "\"ax%5E2%2Bbx%2Bc=0\"\r
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\n" ); document.write( "\n" ); document.write( "the general solution using the quadratic equation is:\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29\"\r
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\n" ); document.write( "\n" ); document.write( "So lets solve \"x%5E2%2B4%2Ax-3=0\" ( notice \"a=1\", \"b=4\", and \"c=-3\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-4+%2B-+sqrt%28+%284%29%5E2-4%2A1%2A-3+%29%29%2F%282%2A1%29\" Plug in a=1, b=4, and c=-3\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-4+%2B-+sqrt%28+16-4%2A1%2A-3+%29%29%2F%282%2A1%29\" Square 4 to get 16 \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-4+%2B-+sqrt%28+16%2B12+%29%29%2F%282%2A1%29\" Multiply \"-4%2A-3%2A1\" to get \"12\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-4+%2B-+sqrt%28+28+%29%29%2F%282%2A1%29\" Combine like terms in the radicand (everything under the square root)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-4+%2B-+2%2Asqrt%287%29%29%2F%282%2A1%29\" Simplify the square root (note: If you need help with simplifying the square root, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-4+%2B-+2%2Asqrt%287%29%29%2F2\" Multiply 2 and 1 to get 2\r
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\n" ); document.write( "\n" ); document.write( "So now the expression breaks down into two parts\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-4+%2B+2%2Asqrt%287%29%29%2F2\" or \"x+=+%28-4+-+2%2Asqrt%287%29%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "Now break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"x=-4%2F2%2B2%2Asqrt%287%29%2F2\" or \"x=-4%2F2-2%2Asqrt%287%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "Simplify\r
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\n" ); document.write( "\n" ); document.write( "\"x=-2%2Bsqrt%287%29\" or \"x=-2-sqrt%287%29\"\r
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\n" ); document.write( "\n" ); document.write( "So these expressions approximate to\r
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\n" ); document.write( "\n" ); document.write( "\"x=0.645751311064591\" or \"x=-4.64575131106459\"\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=0.645751311064591\" or \"x=-4.64575131106459\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"x%5E2%2B4%2Ax-3\", we get:\r
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\n" ); document.write( "\n" ); document.write( "when we use the root finder feature on a calculator, we find that \"x=0.645751311064591\" and \"x=-4.64575131106459\".So this verifies our answer
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