document.write( "Question 119765: Solve using the quadratic formula please:\r
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Algebra.Com's Answer #87769 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "\"3x%5E2-2x=15x-10\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"3x%5E2-2x-15x%2B10=0\" Subtract 15x from both sides. Add 10 to both sides. \r
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\n" ); document.write( "\n" ); document.write( "\"3x%5E2-17x%2B10=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 \"3%2Ax%5E2-17%2Ax%2B10=0\" ( notice \"a=3\", \"b=-17\", and \"c=10\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28--17+%2B-+sqrt%28+%28-17%29%5E2-4%2A3%2A10+%29%29%2F%282%2A3%29\" Plug in a=3, b=-17, and c=10\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2817+%2B-+sqrt%28+%28-17%29%5E2-4%2A3%2A10+%29%29%2F%282%2A3%29\" Negate -17 to get 17\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2817+%2B-+sqrt%28+289-4%2A3%2A10+%29%29%2F%282%2A3%29\" Square -17 to get 289 (note: remember when you square -17, you must square the negative as well. This is because \"%28-17%29%5E2=-17%2A-17=289\".)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2817+%2B-+sqrt%28+289%2B-120+%29%29%2F%282%2A3%29\" Multiply \"-4%2A10%2A3\" to get \"-120\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2817+%2B-+sqrt%28+169+%29%29%2F%282%2A3%29\" Combine like terms in the radicand (everything under the square root)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%2817+%2B-+13%29%2F%282%2A3%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+=+%2817+%2B-+13%29%2F6\" Multiply 2 and 3 to get 6\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+=+%2817+%2B+13%29%2F6\" or \"x+=+%2817+-+13%29%2F6\"\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=%2817+%2B+13%29%2F6\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=30%2F6\" Add the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"x=5\" Divide\r
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\n" ); document.write( "\n" ); document.write( "So one answer is\r
\n" ); document.write( "\n" ); document.write( "\"x=5\"\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=%2817+-+13%29%2F6\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=4%2F6\" Subtract the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"x=2%2F3\" Divide\r
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\n" ); document.write( "\n" ); document.write( "So another answer is\r
\n" ); document.write( "\n" ); document.write( "\"x=2%2F3\"\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=5\" or \"x=2%2F3\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"3%2Ax%5E2-17%2Ax%2B10\", we get:\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-8%2C+15%2C+-8%2C+15%2C3%2Ax%5E2%2B-17%2Ax%2B10%29+\"\r
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\n" ); document.write( "\n" ); document.write( "and we can see that the roots are \"x=5\" and \"x=2%2F3\". This verifies our answer
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