SOLUTION: A projectile is shot straight up from a height of 6m with an initial velocity of 80m/s. Its height in meters above the ground after t seconds is given by the equation h=6+80t-5t^2

Question 1200642: A projectile is shot straight up from a height of 6m with an initial velocity of 80m/s. Its height in meters above the ground after t seconds is given by the equation h=6+80t-5t^2. After how many seconds does the projectile reach its maximum height, and what is this height

Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
A projectile is shot straight up from a height of 6m with an initial velocity of 80m/s. Its height in meters above the ground after t seconds is given by the equation h=6+80t-5t^2. After how many seconds does the projectile reach its maximum height, and what is this height
--------------
h(t) = 6+80t-5t^2
The max of the parabola is at t = -b/2a
--> t = -80/-10 = 8 seconds
----
h(8) = 6 + 80*8 - 5*64 = 326 meters
====================
Or,
h(t) = 6+80t-5t^2
h'(t) = 80 - 10t = 0
t = 8
etc
RELATED QUESTIONS
A projectile is launched straight up from ground level with an initial velocity of 256... (answered by Alan3354)

A projectile is launched straight up from the ground with an initial velocity of 600... (answered by josmiceli)

if a projectile is shot vertically upward from the ground with an initial velocity of 150 (answered by Alan3354)

if a projectile is shot vertically upward from the ground with an initial velocity of 150 (answered by Alan3354,stanbon)

A turkey is shot up into the air from a height of 18 feet above ground level with an... (answered by lwsshak3)

A fireworks shell is shot straight up with an initial velocity of 80 feet per second. Its (answered by lwsshak3,Alan3354,stanbon)

if a projectile is fired straight upward from the ground with an initial speed of 40 ft... (answered by ikleyn)

Height of a Projectile A projectile is fired straight upward from ground level with an... (answered by ankor@dixie-net.com)

using the formula for a path of a projectile h = -4.9t^2 + vt + s where h is the height... (answered by htmentor)