document.write( "Question 92079This question is from textbook Algebra and Trigonometry
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\n" ); document.write( " 5x^2 - 3x - 3 = 0
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Algebra.Com's Answer #66914 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 \"5%2Ax%5E2-3%2Ax-3=0\" ( notice \"a=5\", \"b=-3\", and \"c=-3\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28--3+%2B-+sqrt%28+%28-3%29%5E2-4%2A5%2A-3+%29%29%2F%282%2A5%29\" Plug in a=5, b=-3, and c=-3\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+%28-3%29%5E2-4%2A5%2A-3+%29%29%2F%282%2A5%29\" Negate -3 to get 3\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+9-4%2A5%2A-3+%29%29%2F%282%2A5%29\" Square -3 to get 9 (note: remember when you square -3, you must square the negative as well. This is because \"%28-3%29%5E2=-3%2A-3=9\".)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+9%2B60+%29%29%2F%282%2A5%29\" Multiply \"-4%2A-3%2A5\" to get \"60\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+69+%29%29%2F%282%2A5%29\" Combine like terms in the radicand (everything under the square root)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%2869%29%29%2F10\" Multiply 2 and 5 to get 10\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+=+%283+%2B+sqrt%2869%29%29%2F10\" or \"x+=+%283+-+sqrt%2869%29%29%2F10\"\r
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\n" ); document.write( "\n" ); document.write( "Now break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2B3%2F10%2Bsqrt%2869%29%2F10\" or \"x=%2B3%2F10-sqrt%2869%29%2F10\"\r
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\n" ); document.write( "\n" ); document.write( "So these expressions approximate to\r
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\n" ); document.write( "\n" ); document.write( "\"x=1.13066238629181\" or \"x=-0.530662386291808\"\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=1.13066238629181\" or \"x=-0.530662386291808\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"5%2Ax%5E2-3%2Ax-3\", we get:\r
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\n" ); document.write( "\n" ); document.write( "when we use the root finder feature on a calculator, we find that \"x=1.13066238629181\" and \"x=-0.530662386291808\".So this verifies our answer
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