<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>
Answer:
Domain of piece 1:[) -4,-1
Domain of piece 2: [) -1,1
Domain of piece 3:[] 1,5
Step 2:
Rule for piece 1: y=-x
Rule for piece 2: y=1
Rule for piece 3: y=2-x
Step-by-step explanation:
Correct on Edgen
Answer:
Simple random sampling method is used here.
Step-by-step explanation:
Given is that the evening host of a dinner dance reached into a bowl, mixed all the tickets around, and selected the ticket to award the grand door prize.
We can see that this is a simple random sampling method as every name on the ticket has an equal opportunity to get selected.
Answer:
D. 9%
Step-by-step explanation:
1.04 / 2 = 0.52
2.52 / 4 = 0.63 best 1
4.32 / 8 = 0.54
9.12 / 16 = 0.57 best 2
if base on the best deal 1 - 0.63
(0.63 - 0.57) / 0.63 = 0.0952 (≈ 0.09 i.e 9%)
