Answer:
6 sec
Step-by-step explanation:
when ball return to the ground, h is 0
0=at^2 +bt
0 = -4.9t^2+29.4t
factor: -4.9 times -6 is 29.4
0 = -4.9t(t-6)
set each equation to 0
-4.9t = 0 or t-6=0
t = 0 or t= 6
it's 6 seconds
Answer:
after 6 seconds in the air
Step-by-step explanation:
setting 'h' equal to zero will yield when the ball returns to the ground
you can factor out -4.9t to get:
-4.9t(t - 6) = 0
t = 0 (prior to ball being thrown)
t = 6 (this means, after 6 seconds, the height of the ball is back to zero)
