document.write( "Question 98239: I'm lost. I've included the work I think is right.\r
\n" ); document.write( "\n" ); document.write( "Solve the following quadratic equations. Make sure to show all your work. Use graphing to complete.
\n" ); document.write( "1. 3x2 + 11x – 20 = 0\r
\n" ); document.write( "\n" ); document.write( "• Graphing Method
\n" ); document.write( "• 3x2+11x-20=0
\n" ); document.write( "• 3x2+11x-20+20=0+20
\n" ); document.write( "• 3x2+11x=20
\n" ); document.write( "• X2+11/3=20/3
\n" ); document.write( "•
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Algebra.Com's Answer #71392 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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%2B11%2Ax-20=0\" ( notice \"a=3\", \"b=11\", and \"c=-20\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-11+%2B-+sqrt%28+%2811%29%5E2-4%2A3%2A-20+%29%29%2F%282%2A3%29\" Plug in a=3, b=11, and c=-20\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-11+%2B-+sqrt%28+121-4%2A3%2A-20+%29%29%2F%282%2A3%29\" Square 11 to get 121 \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-11+%2B-+sqrt%28+121%2B240+%29%29%2F%282%2A3%29\" Multiply \"-4%2A-20%2A3\" to get \"240\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-11+%2B-+sqrt%28+361+%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+=+%28-11+%2B-+19%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+=+%28-11+%2B-+19%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+=+%28-11+%2B+19%29%2F6\" or \"x+=+%28-11+-+19%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=%28-11+%2B+19%29%2F6\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=8%2F6\" Add the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"x=4%2F3\" 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%2F3\"\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=%28-11+-+19%29%2F6\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=-30%2F6\" Subtract 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 another answer is\r
\n" ); document.write( "\n" ); document.write( "\"x=-5\"\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=4%2F3\" or \"x=-5\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"3%2Ax%5E2%2B11%2Ax-20\", we get:\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-15%2C+14%2C+-15%2C+14%2C3%2Ax%5E2%2B11%2Ax%2B-20%29+\"\r
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\n" ); document.write( "\n" ); document.write( "and we can see that the roots are \"x=4%2F3\" and \"x=-5\". This verifies our answer
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