SOLUTION: .American astronauts working on a space station on the moon toss a ball into the air. The height of the ball is represented by the equation f(t)=-2.7t^2+13.5t+14 where t represents
Question 1152649: .American astronauts working on a space station on the moon toss a ball into the air. The height of the ball is represented by the equation f(t)=-2.7t^2+13.5t+14 where t represents time in seconds since the ball was thrown and f(t) represents the height of the ball in feet.
a. When will the ball hit the ground? seconds (round to the nearest hundredth)
b. What is the greatest height the ball will reach? feet (round to the nearest hundredth) Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website! f(t)=-2.7t^2+13.5t+14
the vertex or maximum height occurs when t=-b/2a, or -13.5/-5.4 or at 2.5 seconds
f(2.5)=-2.7(6.25)+13.5(2.5+14=30.875 or 30.88 feet maximum height
hits the ground when t=0, and want the only positive root when f(t)=0
can rewrite as 0=2.7t^2-13.5t-14
quadratic formula
t=(1/5.4)(13.5+/- sqrt(13.5^2+(151.2))and that sqrt=18.26
only positive root wanted
t=(1/5.4)(31.76)
=5.88 sec
