Question

3 second is?
ground after is??
pleaseeeee

Answer 1

The height of the ball after 3 seconds is 156 feet.

The ball will be 180 feet above the ground after 2.7 seconds.

Explanation:

A ball is dropped from a platform 300 feet above the ground.

The formula that models the height, h, of an object t seconds after it drops from a height of 300 feet is:

`\large\boxed{h=-16t^2+300}`

To find the height of the ball after 3 seconds, substitute t = 3 into the height formula:

`\begin{aligned}h&=-16(3)^2+300\\\\h&=-16(9)+300\\\\h&=-144+300\\\\h&=156\; \sf ft\end{aligned}`

Therefore, the height of the ball after 3 seconds is 156 feet.

To find the time in seconds that the ball will be 180 feet above the ground, substitute h = 180 into the height formula, and solve for t:

`\begin{aligned}-16t^2+300&=180\\\\-16t^2+300-300&=180-300\\\\-16t^2&=-120\\\\(-16t^2)/(-16)&=(-120)/(-16)\\\\t^2&=7.5\\\\√(t^2)&=\pm√(7.5)\\\\t&=\pm 2.7386127...\\\\t&=\pm 2.7\; \sf s\; (nearest\;tenth)\end{aligned}`

Since time is always positive, we should only use the positive value of t.

Therefore, the ball will be 180 feet above the ground after 2.7 seconds.