document.write( "Question 176934This question is from textbook Algebra 1
\n" ); document.write( ": I would like to know if you would be able to help me with this problem.
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\n" ); document.write( "h= -16t^2+vt+c\r
\n" ); document.write( "\n" ); document.write( "Problem- a child tosses a ball upward with a starting velocity of 10 ft/s from a height of 3 ft.\r
\n" ); document.write( "\n" ); document.write( "b) solve. if not caught how long will the ball be in air? \r
\n" ); document.write( "\n" ); document.write( "Thank you for any help you can offer me!\r
\n" ); document.write( "\n" ); document.write( "Thank you so much!!\r
\n" ); document.write( "\n" ); document.write( "-j2012
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Algebra.Com's Answer #131978 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Since we have a \"starting velocity of 10 ft/s from a height of 3 ft\", this means that \"v=10\" and \"c=3\". So the equation is \"h=+-16t%5E2%2B10t%2B3\"\r
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\n" ); document.write( "\n" ); document.write( "The ball will be in the air as long as the height h is NOT zero (when the ball is on the ground). So if we plug in \"h=0\" and solve for t, we'll find when the ball hits the ground. From there, we can figure out how long it will be in the air.\r
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\n" ); document.write( "\n" ); document.write( "\"h=+-16t%5E2%2B10t%2B3\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"0=+-16t%5E2%2B10t%2B3\" Plug in \"h=0\"\r
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\n" ); document.write( "\n" ); document.write( "Notice we have a quadratic equation in the form of \"at%5E2%2Bbt%2Bc\" where \"a=-16\", \"b=10\", and \"c=3\"\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( "\"t+=+%28-b+%2B-+sqrt%28+b%5E2-4ac+%29%29%2F%282a%29\" Start with the quadratic formula\r
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\n" ); document.write( "\n" ); document.write( "\"t+=+%28-%2810%29+%2B-+sqrt%28+%2810%29%5E2-4%28-16%29%283%29+%29%29%2F%282%28-16%29%29\" Plug in \"a=-16\", \"b=10\", and \"c=3\"\r
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\n" ); document.write( "\n" ); document.write( "\"t+=+%28-10+%2B-+sqrt%28+100-4%28-16%29%283%29+%29%29%2F%282%28-16%29%29\" Square \"10\" to get \"100\". \r
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\n" ); document.write( "\n" ); document.write( "\"t+=+%28-10+%2B-+sqrt%28+100--192+%29%29%2F%282%28-16%29%29\" Multiply \"4%28-16%29%283%29\" to get \"-192\"\r
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\n" ); document.write( "\n" ); document.write( "\"t+=+%28-10+%2B-+sqrt%28+100%2B192+%29%29%2F%282%28-16%29%29\" Rewrite \"sqrt%28100--192%29\" as \"sqrt%28100%2B192%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"t+=+%28-10+%2B-+sqrt%28+292+%29%29%2F%282%28-16%29%29\" Add \"100\" to \"192\" to get \"292\"\r
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\n" ); document.write( "\n" ); document.write( "\"t+=+%28-10+%2B-+sqrt%28+292+%29%29%2F%28-32%29\" Multiply \"2\" and \"-16\" to get \"-32\". \r
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\n" ); document.write( "\n" ); document.write( "\"t+=+%28-10+%2B-+2%2Asqrt%2873%29%29%2F%28-32%29\" Simplify the square root (note: If you need help with simplifying square roots, check out this solver) \r
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\n" ); document.write( "\n" ); document.write( "\"t+=+%28-10%2B2%2Asqrt%2873%29%29%2F%28-32%29\" or \"t+=+%28-10-2%2Asqrt%2873%29%29%2F%28-32%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"t=-0.222\" or \"t=0.847\" Use a calculator to approximate the answers.\r
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\n" ); document.write( "\n" ); document.write( "Since a negative time value does NOT make sense, this means that the only solution is \"t=0.847\"\r
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\n" ); document.write( "\n" ); document.write( "So when the time is approximately 0.847 seconds, the ball will hit the ground. \r
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\n" ); document.write( "\n" ); document.write( "So this means that the ball will be in the air for about 0.847 seconds.
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