A rock is thrown into the air. The height (in feet) of the rock after t seconds is given by

h = -16t^2 + 64t

.

Answer the following algebraically

.

a)

What is the height reached by the ball after 1 second

?

________________________

b

)

Determine the maximum height the rock attains

________________________

c

)

How long it will take to reach

maximum height.

________________________

d

)

When does the rock hit the ground?

kaysteve
Oct 31, 2018

#1**+3 **

When t=1

h= -16(1^2) +64(1) = 48 FT

Max = c- b^2/4a = 0 - (64^2/(4(-16)) = 64 ft

t max 64 = -16t^2 +64t -t^2 +4t -4 = 0 or t^2 -4t+4 = 0 (t-2)(t-2) = 0 so t max = 2 sec

h= 0

0 = -16t^2 + 64t

16t = 64

t= 4 sec

ElectricPavlov
Oct 31, 2018