document.write( "Question 490857: a stone is thrown straight upward with a speed of 20m/s,it is caught on its way down at a point 5.0m above where it was thrown,how far was it going when it was caught,and how long did the trip take \n" ); document.write( "
Algebra.Com's Answer #334341 by ccs2011(207)\"\" \"About 
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Initial velocity = 20
\n" ); document.write( "h(t) = -4.9t^2 +20t
\n" ); document.write( "Solve for t when h(t) = 5
\n" ); document.write( "--> \"-4.9t%5E2+%2B20t+=+5\"
\n" ); document.write( "--> \"-4.9t%5E2+%2B20t+-5+=+0\"
\n" ); document.write( "-----------------------------------
\n" ); document.write( "Use quadratic formula
\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29\"
\n" ); document.write( "---------------------------------
\n" ); document.write( "-->
\n" ); document.write( "--> \"t+=+%28-20+%2B-+sqrt%28302%29%29%2F%28-9.8%29\"
\n" ); document.write( "--> \"t+=+%2820+%2B-+sqrt%28302%29%29%2F9.8+\"
\n" ); document.write( "We want the time when the stone is on its way down which will be the longer time
\n" ); document.write( "--> \"t+=+%2820+%2B+sqrt%28302%29%29%2F9.8+=+3.814\"
\n" ); document.write( "Trip took 3.814 sec
\n" ); document.write( "-------------------------------------
\n" ); document.write( "v(t) = -9.8t + 20
\n" ); document.write( "Solve for when t = 3.814
\n" ); document.write( "--> \"v+=+%28-9.8%29%283.814%29+%2B+20+=+-17.378\"
\n" ); document.write( "Speed is always positive
\n" ); document.write( "Stone was traveling at 17.378 m/s when caught
\n" ); document.write( "
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