A firework rocket is shot upward at a rate of 640ft/sec. Use the projectile formula h = - 16t^2 + v0t to determine the times when the height of the firework will be 1,200 feet. Round your answer to the nearest whole number.

2 seconds and 38 seconds

Step-by-step explanation:

h=-16t²-vot

1,200=-16t²-640t

turn this into standard form

16t²-640t+1200=0

now plug thes numbers into the quadratice formula

a 16 b - 640 c 1200

solve with quadratic formula to get ≅2 and ≅38 seconds