document.write( "Question 90110: solve the following quadratic equation\r
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Algebra.Com's Answer #65422 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"4x%5E2=13x%2B12\"\r
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\n" ); document.write( "\n" ); document.write( "\"0=-4x%5E2%2B13x%2B12\" Subtract 4x^2 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 \"-4%2Ax%5E2%2B13%2Ax%2B12=0\" ( notice \"a=-4\", \"b=13\", and \"c=12\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-13+%2B-+sqrt%28+%2813%29%5E2-4%2A-4%2A12+%29%29%2F%282%2A-4%29\" Plug in a=-4, b=13, and c=12\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-13+%2B-+sqrt%28+169-4%2A-4%2A12+%29%29%2F%282%2A-4%29\" Square 13 to get 169 \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-13+%2B-+sqrt%28+169%2B192+%29%29%2F%282%2A-4%29\" Multiply \"-4%2A12%2A-4\" to get \"192\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-13+%2B-+sqrt%28+361+%29%29%2F%282%2A-4%29\" Combine like terms in the radicand (everything under the square root)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-13+%2B-+19%29%2F%282%2A-4%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+=+%28-13+%2B-+19%29%2F-8\" Multiply 2 and -4 to get -8\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+=+%28-13+%2B+19%29%2F-8\" or \"x+=+%28-13+-+19%29%2F-8\"\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=%28-13+%2B+19%29%2F-8\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=6%2F-8\" Add the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"x=-3%2F4\" Divide\r
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\n" ); document.write( "\n" ); document.write( "So one answer is\r
\n" ); document.write( "\n" ); document.write( "\"x=-3%2F4\"\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=%28-13+-+19%29%2F-8\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=-32%2F-8\" Subtract the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"x=4\" Divide\r
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\n" ); document.write( "\n" ); document.write( "So another answer is\r
\n" ); document.write( "\n" ); document.write( "\"x=4\"\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=-3%2F4\" or \"x=4\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"-4%2Ax%5E2%2B13%2Ax%2B12\", we get:\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-13%2C+14%2C+-13%2C+14%2C-4%2Ax%5E2%2B13%2Ax%2B12%29+\"\r
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\n" ); document.write( "\n" ); document.write( "and we can see that the roots are \"x=-3%2F4\" and \"x=4\". This verifies our answer
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