240 is probably multiplied some other number if theres another number on there to multiply or divide by.
<span>First of all, there should be coherence for the units of measurement -- either they are all meters or they are all ft. I would assume they are all ft.
The correct answer is 75 ft above. T
The explanation is the following: suppose the ground level is the x-axis, the 2 feet of the arch lie respectively on (0,0) and (100,0) on the ground level. Since the arch is 100ft high, the vertex of the parabola will be the point (100,100). Thus, we can find the equation describing the parabola by putting the three points we know in a system and we find that the equation of the parabola is y=(-1/100)x^2+2
To find the focus F, we apply the formula for the focus of a vertical axis parabola, i.e. F(-b/2a;(1-b^2+4ac)/4a).
By substituting a=-1/100, b=2 and c=0 into the formula, we find that the coordinates of the focus F are (100,75).
So we conclude that the focus lies 75ft above ground.</span>
![\bf ~~~~~~\textit{initial velocity} \\\\ \begin{array}{llll} ~~~~~~\textit{in feet} \\\\ h(t) = -16t^2+v_ot+h_o \end{array} \quad \begin{cases} v_o=\stackrel{64}{\textit{initial velocity of the object}}\\\\ h_o=\stackrel{0\qquad \textit{from the ground}}{\textit{initial height of the object}}\\\\ h=\stackrel{}{\textit{height of the object at "t" seconds}} \end{cases} \\\\[-0.35em] \rule{34em}{0.25pt}](https://tex.z-dn.net/?f=%5Cbf%20~~~~~~%5Ctextit%7Binitial%20velocity%7D%20%5C%5C%5C%5C%20%5Cbegin%7Barray%7D%7Bllll%7D%20~~~~~~%5Ctextit%7Bin%20feet%7D%20%5C%5C%5C%5C%20h%28t%29%20%3D%20-16t%5E2%2Bv_ot%2Bh_o%20%5Cend%7Barray%7D%20%5Cquad%20%5Cbegin%7Bcases%7D%20v_o%3D%5Cstackrel%7B64%7D%7B%5Ctextit%7Binitial%20velocity%20of%20the%20object%7D%7D%5C%5C%5C%5C%20h_o%3D%5Cstackrel%7B0%5Cqquad%20%5Ctextit%7Bfrom%20the%20ground%7D%7D%7B%5Ctextit%7Binitial%20height%20of%20the%20object%7D%7D%5C%5C%5C%5C%20h%3D%5Cstackrel%7B%7D%7B%5Ctextit%7Bheight%20of%20the%20object%20at%20%22t%22%20seconds%7D%7D%20%5Cend%7Bcases%7D%20%5C%5C%5C%5C%5B-0.35em%5D%20%5Crule%7B34em%7D%7B0.25pt%7D)
Check the picture below, it hits the ground at 0 feet, where it came from, the ground, and when it came back down.
The +k part of the function takes the original function and translates it straight up k units. It's as simple as that. If your function is the line f(x) = 3x, then the function f(x) = 3x + 4 moves that first function up 4 units.
