I'm quite confused!

[superhumann]

So my teacher has given me a homework problem that I seem to not understand. I've tried everything and I can't get it please help.
My attempt:
t = 102 / 32 ; h(102 / 32 ) ; h(t) = 0 ...102 / 16

A football is kicked from the ground with an initial velocity of 84 feet per second. The equation that models the situations is h(t)=-16t^2+102t where h(t) represents the height of the football in feet and t represents the time in seconds.

a. when does the football reach its max. height?

b. what is the max height of graph?

c. when does it hit the ground?

d. what is the domain of this situation?

e. what is the range of this equation?

 

[Deleted member 4993]

So my teacher has given me a homework problem that I seem to not understand. I've tried everything and I can't get it please help.
My attempt:
t = 102 / 32 ; h(102 / 32 ) ; h(t) = 0 ...102 / 16

A football is kicked from the ground with an initial velocity of 84 feet per second. The equation that models the situations is h(t)=-16t^2+102t where h(t) represents the height of the football in feet and t represents the time in seconds.

a. when does the football reach its max. height?

b. what is the max height of graph?

c. when does it hit the ground?

d. what is the domain of this situation?

e. what is the range of this equation?

Since you tried multiple times, then:

please tell us what are your thoughts?

Please share your work with us ...even if you know it is wrong

If you are stuck at the beginning tell us and we'll start with the definitions.

You need to read the rules of this forum. Please read the post titled "Read before Posting" at the following URL:

http://www.freemathhelp.com/forum/th...Before-Posting

 

[stapel]

So my teacher has given me a homework problem that I seem to not understand. I've tried everything and I can't get it please help.
My attempt: t = 102 / 32 ; h(102 / 32 ) ; h(t) = 0 ...102 / 16

Unfortunately, it is not possible to find errors or provide explanations when all we can see are the final results. Sorry!

A football is kicked from the ground with an initial velocity of 84 feet per second. The equation that models the situations is h(t)=-16t^2+102t where h(t) represents the height of the football in feet and t represents the time in seconds.

a. when does the football reach its max. height?

You are given a quadratic. Its equation is negative, so its parabola is upside-down. Where, then, is the maximum?

Note: Since the equation is for h in terms of t, the vertex is at (t, h(t)), where of course t is the time (the "when") and h is the height (the "how high").

b. what is the max height of graph?

See the answer for part (a).

c. when does it hit the ground?

What is the "height above ground" when the ball is on the ground? Find the time t for that height h.

d. what is the domain of this situation?

Assuming "this situation" is the word problem, rather than the function, then what domain (in terms of time) makes sense (based on the physical limitations of height and time)?

e. what is the range of this equation?

The range is the heights. The parabola, as you know, goes below the x-axis. But does this make sense for "this situation"? Also, there is a maximum (both for the function and for "this situation"). This impacts the range, also.