document.write( "Question 388858: Can someone help me with this problem. I do not understand it I am lost.\r
\n" ); document.write( "\n" ); document.write( "Solving a word problem using a quadratic equation with irrational roots
\n" ); document.write( "When a ball is thrown, its height in feet h after t seconds is given by the equation
\n" ); document.write( "h=vt-16t^2
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\n" ); document.write( "where is the initial upwards velocity in feet per second. If v = 36 feet per second, find all values of t for which h = 19 feet. Do not round any intermediate steps. Round your answer to decimal places.
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\n" ); document.write( "\n" ); document.write( "Thank you very much.
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Algebra.Com's Answer #275268 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
When a ball is thrown, its height in feet h after t seconds is given by the
\n" ); document.write( " equation h = vt - 16t^2, where is the initial upwards velocity in feet per second.
\n" ); document.write( " If v = 36 feet per second, find all values of t for which h = 19 feet.
\n" ); document.write( " Do not round any intermediate steps. Round your answer to decimal places ??
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\n" ); document.write( "Using the given equation, replace v with 36, and h with 19
\n" ); document.write( "36t - 16t^2 = 19
\n" ); document.write( "Arrange this as a quadratic equation
\n" ); document.write( "0 = 16t^2 - 36t + 19
\n" ); document.write( "Solve this using the quadratic equation (ax^2 + bx + c)
\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
\n" ); document.write( "Let x=t, a=16, b=-36, c= 19
\n" ); document.write( "\"t+=+%28-%28-36%29+%2B-+sqrt%28-36%5E2-4%2A16%2A19+%29%29%2F%282%2A16%29+\"
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\n" ); document.write( "\"t+=+%2836+%2B-+sqrt%281296-1216+%29%29%2F32+\"
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\n" ); document.write( "Two solutions
\n" ); document.write( "\"t+=+%2836+%2B+sqrt%2880%29%29%2F32+\"
\n" ); document.write( "t = 1.404508 sec
\n" ); document.write( "and
\n" ); document.write( "\"t+=+%2836+-+sqrt%2880%29%29%2F32+\"
\n" ); document.write( "t = .845915 sec
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\n" ); document.write( "We can say the ball is at 19 ft ~ .8 sec on the way up and ~ 1.4 sec on the way down \n" ); document.write( "
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