document.write( "Question 92553: solve each of teh quadratic equation\r
\n" ); document.write( "\n" ); document.write( "4x^2 = 13x + 12
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Algebra.Com's Answer #67374 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"4x%5E2+=+13x+%2B+12\"\r
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\n" ); document.write( "\n" ); document.write( "\"4x%5E2+-13x+-+12=0\" get all terms to one side\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%5E2-13%2Ax-12=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+%28-13%29%5E2-4%2A4%2A-12+%29%29%2F%282%2A4%29\" Plug in a=4, b=-13, and c=-12\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2813+%2B-+sqrt%28+%28-13%29%5E2-4%2A4%2A-12+%29%29%2F%282%2A4%29\" Negate -13 to get 13\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2813+%2B-+sqrt%28+169-4%2A4%2A-12+%29%29%2F%282%2A4%29\" Square -13 to get 169 (note: remember when you square -13, you must square the negative as well. This is because \"%28-13%29%5E2=-13%2A-13=169\".)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2813+%2B-+sqrt%28+169%2B192+%29%29%2F%282%2A4%29\" Multiply \"-4%2A-12%2A4\" to get \"192\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2813+%2B-+sqrt%28+361+%29%29%2F%282%2A4%29\" Combine like terms in the radicand (everything under the square root)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2813+%2B-+19%29%2F%282%2A4%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+=+%2813+%2B-+19%29%2F8\" 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+=+%2813+%2B+19%29%2F8\" or \"x+=+%2813+-+19%29%2F8\"\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=%2813+%2B+19%29%2F8\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=32%2F8\" Add 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 one answer is\r
\n" ); document.write( "\n" ); document.write( "\"x=4\"\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=%2813+-+19%29%2F8\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=-6%2F8\" Subtract 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 another answer is\r
\n" ); document.write( "\n" ); document.write( "\"x=-3%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=4\" or \"x=-3%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"4%2Ax%5E2-13%2Ax-12\", 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%2C4%2Ax%5E2%2B-13%2Ax%2B-12%29+\"\r
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\n" ); document.write( "\n" ); document.write( "and we can see that the roots are \"x=4\" and \"x=-3%2F4\". This verifies our answer
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