document.write( "Question 1141693: You are hitting baseballs. When tossing the ball into the air, your hand is 5
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Algebra.Com's Answer #762279 by Edwin McCravy(20054)\"\" \"About 
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You are hitting baseballs. When tossing the ball into the air, your hand is 5
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document.write( "The formula for the height above the ground is\r\n" );
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document.write( "\"h=h%5B0%5D%2Bv%5B0%5D%2At-16t%5E2\"\r\n" );
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document.write( "where h = final height above ground when time = t.\r\n" );
document.write( "      ho = initial height above ground = 5 ft\r\n" );
document.write( "      vo = initial velocity = 25 ft/s.\r\n" );
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document.write( "The two variables are h and t.\r\n" );
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document.write( "We want to find t when h = 4\r\n" );
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document.write( "\"4=5%2B25%2At-16t%5E2\"\r\n" );
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document.write( "Get in descending order:\r\n" );
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document.write( "\"16t%5E2-25%2At-1=0\"\r\n" );
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document.write( "Unfortunately that doesn't factor, so we use the\r\n" );
document.write( "quadratic formula:\r\n" );
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document.write( "\"t+=+%28-b+%2B-+sqrt%28+b%5E2-4ac+%29%29%2F%282a%29+\", a=16, b=-25, c=-1\r\n" );
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document.write( "\"t+=+%28-%28-25%29+%2B-+sqrt%28+%28-25%29%5E2-4%2816%29%28-1%29+%29%29%2F%282%2816%29%29+\"\r\n" );
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document.write( "\"t+=+%2825+%2B-+sqrt%28625%2B64+%29%29%2F32+\"\r\n" );
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document.write( "\"t+=+%2825+%2B-+sqrt%28689%29%29%2F32+\" \r\n" );
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document.write( "\"t=1.601525297\" and \"t=-0.0390252968\"\r\n" );
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document.write( "We ignore the negative answer.\r\n" );
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document.write( "Answer:  t = 1.6 seconds (rounded to 1 decimal place).\r\n" );
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document.write( "Edwin
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