SOLUTION: A toy glider is tossed into the air. Its height, h, in metres, after t seconds is modelled by h = 9t � 3t2. Find the maximum height the toy glider reaches. Show the steps of your s

Question 702019: A toy glider is tossed into the air. Its height, h, in metres, after t seconds is modelled by h = 9t � 3t2. Find the maximum height the toy glider reaches. Show the steps of your solution.

Answer by nerdybill(7384) (Show Source): You can put this solution on YOUR website!
A toy glider is tossed into the air. Its height, h, in metres, after t seconds is modelled by h = 9t � 3t2. Find the maximum height the toy glider reaches. Show the steps of your solution.
.
The equation:
h = 9t � 3t^2
can be written as:
h = �3t^2 + 9t
is a parabola that opens downwards (based on the negative coefficient associated with the t^2 term). This means that the max will be at the vertex:
Find t value of the vertex:
t = -b/(2a)
t = -9/(2(-3))
t = -9/(-6)
t = 3/2 seconds
.
To find the height, we plug the value above back into the original equation:
h = �3t^2 + 9t
h = �3(3/2)^2 + 9(3/2)
h = �3(9/4) + 9(3/2)
h = �27/4 + 27/2
h = �27/4 + 54/4
h = (�27+54)/4
h = 27/4
h = 6.75 meters

RELATED QUESTIONS
A football is kicked into the air. The height of the football is modelled by... (answered by ikleyn)

A ball is shot into the air. Its height h, in metres, after t seconds is modelled by... (answered by ikleyn)

2. A toy rocket is fired into the air from the top of a barn. Its height (h) above the... (answered by Boreal)

A toy rocket is launched in an open field. The path of the rocket can be modelled by the... (answered by ikleyn)

4. A video tracking device recorded the height h, in metres, of a baseball after it was... (answered by ikleyn)

A football is kicked into the air. The height of the football is modelled by... (answered by josmiceli,Natolino1983)

A video tracking device recorded the height h, in metres, of a baseball after it was hit... (answered by josgarithmetic,MathTherapy,ikleyn)

A baseball is hit to centre field. The ball�s height h, in metres, after t seconds can be (answered by Fombitz)

A stone is tossed from a bridge into the river below. Its path is represented by h =... (answered by MathLover1,ikleyn)