Please help me (:

If an object is dropped from a height of 200 feet, the function h(t) = -16t^2 + 200 gives the height of the object after t seconds. Approximately when will the object hit the ground?

a. 2000.00 seconds
b. 184.00 seconds
c. 3.54 seconds
d. 0.78 seconds

Question

Please help me (:

If an object is dropped from a height of 200 feet, the function h(t) = -16t^2 + 200 gives the height of the object after t seconds. Approximately when will the object hit the ground?

a. 2000.00 seconds
b. 184.00 seconds
c. 3.54 seconds
d. 0.78 seconds

campbell_st · Answer

well it hits the ground when h = 0 and you need to find the time needed... 

so 

$$0 = -16t^2 + 200$$

so just solve 

$$16t^2 = 200$$

only consider the positive value of t since time can't be negative.