Question 829633
the height in feet of a bottle rocket is given by h(t)=160t-t2 where t is the time in seconds. How long will it take for the rocket to return to the ground? 
***
When the rocket returns to the ground,its height=0
h(t)=160t-t2
0=160t-t2
-t^2+160t=0
-t(t-160)=0
t=0(reject,t>0)
or
t-160=0
t=160
How long will it take for the rocket to return to the ground? 160 seconds