# SOLUTION: The equation h=-16t^2-32t+320 Give the height of a ball, thrown donward from top of a 320ft. Building with an initial velocity of 32ft/s. Find the time it takes for the ball to

Algebra ->  Algebra  -> Customizable Word Problem Solvers  -> Misc -> SOLUTION: The equation h=-16t^2-32t+320 Give the height of a ball, thrown donward from top of a 320ft. Building with an initial velocity of 32ft/s. Find the time it takes for the ball to       Log On

 Ad: Over 600 Algebra Word Problems at edhelper.com Ad: Algebra Solved!™: algebra software solves algebra homework problems with step-by-step help! Ad: Algebrator™ solves your algebra problems and provides step-by-step explanations!

 Word Problems: Miscellaneous Word Problems Solvers Lessons Answers archive Quiz In Depth

 Click here to see ALL problems on Miscellaneous Word Problems Question 124439: The equation h=-16t^2-32t+320 Give the height of a ball, thrown donward from top of a 320ft. Building with an initial velocity of 32ft/s. Find the time it takes for the ball to reach a height of 64ft.Answer by checkley71(8403)   (Show Source): You can put this solution on YOUR website!H=-16T^2-32T+320 64=-16T^2-32T+320 -16T^2-32T+320-64=0 -16T^2-32T+256=0 -16(T^2+2T-16)=0 USING THE QUADRATIC EQUATION: X=(-2+-SQRT[2^2-4*1*-16])/2*1 X=(-2+-SQRT[4+64])/2 X=(-2+-SQRT68)/2 X=(-2+-8.246)/2 X=(-2+8.246)/2 X=6.246/2 X=3.123 SECONDS. ANSWER FOR THE TIME FOR THE BALL TO BE @ 64 FT FROM THE GROUND.