document.write( "Question 118217: Hello, I am having problems understanding the steps used to solve equations using the quadratic formula. Can you please show me detailed steps to understand how to solve this problem. All help is greatly appreciated, thank you.\r
\n" ); document.write( "\n" ); document.write( "My directions say to use the quadratic formula to solve.\r
\n" ); document.write( "\n" ); document.write( "3x^2 – 2x = 15x – 10\r
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\n" ); document.write( "Patti
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Algebra.Com's Answer #86320 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\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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