Homework Help: Math

Posted by Rutba on Sunday, October 28, 2012 at 2:05pm.

a firecracker is fired from the ground. The height of the firecracker at a given time is modeled by the function h(t) =-5t^2+50t, where h(t) is the height in metres and t is the time in seconds. When will the firecracker reach a height of 45m ?

Math - Steve, Sunday, October 28, 2012 at 8:54pm
solve for t in

45 = -5t^2 + 50t
5t^2 - 50t + 45 = 0
t^2 - 10t + 9 = 0
(t-9)(t-1) = 0

it will reach 45m on the way up at t=1, and on the way back down at t=9.

Answer this Question

Related Questions

Math - A firecracker is launched straight up, and its height is a function of ...
Math - 11. A rocket is fired upward from some initial height above the ground. ...
Physics - a) A cannonball is fired horizontally from the top of a cliff. The ...
physics - Consider a projectile fired horizontally from a cliff of a given ...
MATH - The path of a large stone fired from a catapult can be modeled by y= -0....
science - I am having trouble with my homework it tells me to write the diffrent...
Math B - The path of a rocket fired during a fireworks display is given by the ...
Math - A clown was shot out of a cannon at ground level. Her height above the ...
science - is a firecracker exploding great example of potential energy or can I ...
Math - A projectile is fired straight up from a cliff which is 200 feet above ...

For Further Reading

First Name:
School Subject:
Answer: