The distance that an object falls varies directly as the square of the time it has been falling. An object falls 65 feet in 2 seconds. Find how far it will fall in 5 seconds?

Question

darkbluechocobo · Answer

406 feet
	
13 feet
	
25 feet
	
325 feet

phi · Answer

distance varies directly as t^2
means there is an equation

d= k t^2
you need to first find "k"  using the info 65 feet in 2 seconds
then you can find d when t is 5

darkbluechocobo · Answer

65= k 4?

darkbluechocobo · Answer

oh wait it would be plugging in t for 5 so 65=k25

phi · Answer

yes,  
65= k 4
divide both sides by 4 to get
k= 65/4

now you know

$$ d= \frac{65}{4} t^2 $$

for t=5 , replace t with 5:
$$ d= \frac{65}{4}5^2 $$
and simplify

darkbluechocobo · Answer

65/4 = 16.25*25= 406.25 so 406

phi · Answer

yes, it looks like they rounded to the nearest foot.

darkbluechocobo · Answer

yes Well thank you for going through that :)

phi · Answer

sorry I lost track of this one, and forgot to get back to you.

darkbluechocobo · Answer

aha its fine :3