A rock falls from a tower that is 320 feet high. As it is falling, its height is given by the formula h equals 320 minus 16 t squared . How many seconds (in tenths) will it take for the rock to hit the ground (hequals0)?

a. 4.5secs

Explanation:

From the question, the equation describing the height is given by

at the point when the rock hit the ground, the height,h will be zero.

Hence we can have

hence the rock will hit the ground in 4.5secs

we have been given a quadratic function and we need to restrict the domain such that it becomes a one to one function.

we know that vertex of this quadratic function occurs at (5,2).

further, we know that range of this function is .

if we restrict the domain of this function to either or , it will become one to one function.

let us know find its inverse.

upon interchanging x and y, we get:

let us now solve this function for y.

hence, the inverse function would be if we restrict the domain of original function to and the inverse function would be if we restrict the domain to .