Please. Need help with quadratic word problem

AI Thread Summary
The discussion focuses on solving a quadratic word problem involving an object launched from a height. Key points include determining the equation of motion, calculating the object's height after 3 seconds, and identifying the time span it remains above 40 meters. Additionally, the maximum height and the time taken to reach it, as well as the time to hit the ground, are also addressed. The conversation emphasizes using the initial conditions and acceleration due to gravity to derive the necessary calculations.
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Please. Need help with quadratic word problem!

PLEASE HELP WITH THIS!
An object is launched upward at 9.8 meters per second (m/s) from a 39.2-meter tall platform.

a)write an equation representing this path

b) What is the height of the object after 3 seconds

c) For what time span is the object more than 40 meters above the ground?

d) what is the maximum height of the object

e) how long did it take for the object to reach maximum height

f) how long does it take for the object to hit the ground

g) State the practical domain

h) state the practical range
 
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please help me with this!
 


to get you started...

b) you know that the acceleration is - 9.8m/s^2 ( as its going against gravity), the initial velocity is 9.8 m/s and the time is 3s and you want out find its height. so use an equation that has all 4 of these into calculate the height and then add the initial 39.2m height onto this answer to give you your total max hieght.
 

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