document.write( "Question 130756: Find the exact solutions to \"x%5E2%2B4x%2B4=16\" \n" ); document.write( "
Algebra.Com's Answer #95468 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"x%5E2%2B4x%2B4=16\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B4x%2B4-16=0\" Subtract 16 from both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2B4x-12=0\" Combine like terms\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-12=0\" ( notice \"a=1\", \"b=4\", and \"c=-12\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-4+%2B-+sqrt%28+%284%29%5E2-4%2A1%2A-12+%29%29%2F%282%2A1%29\" Plug in a=1, b=4, and c=-12\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-4+%2B-+sqrt%28+16-4%2A1%2A-12+%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%2B48+%29%29%2F%282%2A1%29\" Multiply \"-4%2A-12%2A1\" to get \"48\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-4+%2B-+sqrt%28+64+%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-+8%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-+8%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+8%29%2F2\" or \"x+=+%28-4+-+8%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "Lets look at the first part:\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-4+%2B+8%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=4%2F2\" Add the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"x=2\" Divide\r
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\n" ); document.write( "\n" ); document.write( "So one answer is\r
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\n" ); document.write( "\n" ); document.write( "Now lets look at the second part:\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-4+-+8%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=-12%2F2\" Subtract the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"x=-6\" Divide\r
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\n" ); document.write( "\n" ); document.write( "So another answer is\r
\n" ); document.write( "\n" ); document.write( "\"x=-6\"\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 exact solutions are:\r
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\n" ); document.write( "\n" ); document.write( "\"x=-6\" or \"x=2\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"x%5E2%2B4%2Ax-12\", we get:\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-16%2C+12%2C+-16%2C+12%2C1%2Ax%5E2%2B4%2Ax%2B-12%29+\"\r
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\n" ); document.write( "\n" ); document.write( "and we can see that the roots are \"x=-6\" and \"x=2\". This verifies our answer\r
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