document.write( "Question 812162: A goalie kicks a soccer ball with an upward velocity of 65 feet per second, and her foot meets the ball 1 foot off the ground. The quadratic function h=16tsquared + 65t + 1 represents the height of the ball h in feet after t seconds. Approximately how long is the ball in the air? \n" ); document.write( "
Algebra.Com's Answer #489036 by brysca(112)![]() ![]() You can put this solution on YOUR website! This relates to the physics equation, Y=Yo+Vot+.5at^2 \n" ); document.write( "This equation is not factorable, so there is no other option to use except through the quadratic formula. (I think the problem may have been typed wrong, so I am making the \"a\" value -16 instead of 16.) \n" ); document.write( "The equation can be re-written as this: \n" ); document.write( "-16t^2+65t+1=0 \n" ); document.write( "a=-16 \n" ); document.write( "b=65 \n" ); document.write( "c=1 \n" ); document.write( "Now, we use the quadratic formula, which is \n" ); document.write( " \n" ); document.write( "and plug in the respective variables. \n" ); document.write( " \n" ); document.write( "This simplifes to \n" ); document.write( "Nothing can be simplified in the above equation so if you plug in the numbers, your answer should be \n" ); document.write( "t=-0.0153267912541177, 4.07782679125412 because there's always two answers in quadratics. \n" ); document.write( "Time obviously cannot be negative so the answer you are left with is t=4.07782679125412. \n" ); document.write( "Or you can just say t equals about 4 seconds.\r \n" ); document.write( "\n" ); document.write( "Cheers, \n" ); document.write( "-Bryan \n" ); document.write( " |