the equationf(x)=16x

2

+v

0

x+h

to show the path of a free-falling object:

• x
• represents time
• v
• 0
• represents the initial velcotiy of the object
• h
• represents the initial height of the object (in feet)
• The input of the function(x)
• represents how long the object has been in the air
• the output of the function is the final height of the object above the ground

Ramzen stood on a rope bridge over a deep cavern and wondered how high the bridge was above the water. He dropped a rock and it took 4.5 seconds to hit the water. When he arrived safely back home he wanted to tell people how high the bridge was, so he used Galileo's equation to estimate the height of the bridge by figuring that when he dropped the stone it had no initial velocity, but gained speed as it fell for the 4.5 seconds to hit the water which he figured was a height of 0. Substituting these figures into Galileo's equation gave him0=16(4.5)

2

+h

. Solving forh

he estimatedthe height of the bridge was:

(a)1,458 feet

(b).790 feet

(c)202.5 feet

(d)1.27 feet

(e)324 feet