SOLUTION: The function F(T) = -5T^2 + 10T + 40 models the height of a rocket shot into the air from a platform, where is the height of the rocket from the ground, in metres, and t is the t

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Question 1159133: The function F(T) = -5T^2 + 10T + 40 models the height of a rocket shot into the air from a platform, where
is the height of the rocket from the ground, in metres, and t is the time in seconds.
a. what is the height of the platform?
b. when does the rocket land?

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
the height of the platform is the constant 40 m.
the landing point is found by taking the positive root of -5t^2+10t+40=0
or t^2-2t-8=0
(t-4)(t+2)=0
t= 4 seconds
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