SOLUTION: An arrow is launched upward. After t seconds,it's height(h)is given by the formula h= -16t^2 + 208t. after how many seconds will it's height be 640 ft.? Should this be solved by

Question 34584: An arrow is launched upward. After t seconds,it's height(h)is given by the formula h= -16t^2 + 208t. after how many seconds will it's height be 640 ft.?
Should this be solved by zero-factor theorem?

Answer by longjonsilver(2297) (Show Source): You can put this solution on YOUR website!
i have answered this question...look at my recent answered questions for the solution.

Jon.