document.write( "Question 132818: Hello
\n" ); document.write( "I hope someone can help me. Here is the question: THe position of an object moving in a straight line is given by s= 2t^2 - 3t, where s is in meters and t is the time in seconds the object has been in motion. How long (to the nearest tenth) wiil it take the object to move 17 meters?
\n" ); document.write( "I am so lost! SO far what I have gotten from this is:
\n" ); document.write( "17= 2t^2 - 3t
\n" ); document.write( "2t^2 - 3t - 17= 0 But now what do I do? Please help-THank you!
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Algebra.Com's Answer #97060 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"17=2t%5E2-3t\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"17=2t%5E2-3t\" Plug in \"s=17\"\r
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\n" ); document.write( "\n" ); document.write( "\"0=2t%5E2-3t-17\" Subtract 17 from both sides. \r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for t:\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( "\"at%5E2%2Bbt%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( "\"t+=+%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 \"0=2%2At%5E2-3%2At-17\" ( notice \"a=2\", \"b=-3\", and \"c=-17\")\r
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\n" ); document.write( "\n" ); document.write( "\"t+=+%28--3+%2B-+sqrt%28+%28-3%29%5E2-4%2A2%2A-17+%29%29%2F%282%2A2%29\" Plug in a=2, b=-3, and c=-17\r
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\n" ); document.write( "\n" ); document.write( "\"t+=+%283+%2B-+sqrt%28+%28-3%29%5E2-4%2A2%2A-17+%29%29%2F%282%2A2%29\" Negate -3 to get 3\r
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\n" ); document.write( "\n" ); document.write( "\"t+=+%283+%2B-+sqrt%28+9-4%2A2%2A-17+%29%29%2F%282%2A2%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( "\"t+=+%283+%2B-+sqrt%28+9%2B136+%29%29%2F%282%2A2%29\" Multiply \"-4%2A-17%2A2\" to get \"136\"\r
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\n" ); document.write( "\n" ); document.write( "\"t+=+%283+%2B-+sqrt%28+145+%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( "\"t+=+%283+%2B-+sqrt%28145%29%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( "\"t+=+%283+%2B+sqrt%28145%29%29%2F4\" or \"t+=+%283+-+sqrt%28145%29%29%2F4\"\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( "\"t=3.76039864469807\" or \"t=-2.26039864469807\"\r
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\n" ); document.write( "\n" ); document.write( "So our possible solutions are:\r
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\n" ); document.write( "\n" ); document.write( "\"t=3.76039864469807\" or \"t=-2.26039864469807\"\r
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\n" ); document.write( "\n" ); document.write( "However, since a negative time doesn't make sense, our only solution is \"t=3.76039864469807\"\r
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\n" ); document.write( "\n" ); document.write( "So it takes about 3.76 seconds for the object to move 17 meters\r
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