document.write( "Question 124298: Use the quadratic formula to solve the following quadratic equation.
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Algebra.Com's Answer #91094 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"2x%5E2-5x=3\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"2x%5E2-5x-3=0\" Subtract 3 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 \"2%2Ax%5E2-5%2Ax-3=0\" ( notice \"a=2\", \"b=-5\", and \"c=-3\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28--5+%2B-+sqrt%28+%28-5%29%5E2-4%2A2%2A-3+%29%29%2F%282%2A2%29\" Plug in a=2, b=-5, and c=-3\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%285+%2B-+sqrt%28+%28-5%29%5E2-4%2A2%2A-3+%29%29%2F%282%2A2%29\" Negate -5 to get 5\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%285+%2B-+sqrt%28+25-4%2A2%2A-3+%29%29%2F%282%2A2%29\" Square -5 to get 25 (note: remember when you square -5, you must square the negative as well. This is because \"%28-5%29%5E2=-5%2A-5=25\".)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%285+%2B-+sqrt%28+25%2B24+%29%29%2F%282%2A2%29\" Multiply \"-4%2A-3%2A2\" to get \"24\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%285+%2B-+sqrt%28+49+%29%29%2F%282%2A2%29\" Combine like terms in the radicand (everything under the square root)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%285+%2B-+7%29%2F%282%2A2%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+=+%285+%2B-+7%29%2F4\" Multiply 2 and 2 to get 4\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+=+%285+%2B+7%29%2F4\" or \"x+=+%285+-+7%29%2F4\"\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=%285+%2B+7%29%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=12%2F4\" Add the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"x=3\" 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\"\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=%285+-+7%29%2F4\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=-2%2F4\" Subtract the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"x=-1%2F2\" Divide\r
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\n" ); document.write( "\n" ); document.write( "So another answer is\r
\n" ); document.write( "\n" ); document.write( "\"x=-1%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=3\" or \"x=-1%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"2%2Ax%5E2-5%2Ax-3\", we get:\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-11%2C+13%2C+-11%2C+13%2C2%2Ax%5E2%2B-5%2Ax%2B-3%29+\"\r
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\n" ); document.write( "\n" ); document.write( "and we can see that the roots are \"x=3\" and \"x=-1%2F2\". This verifies our answer\r
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