<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>
450,000 is your answer:) hope I helped
9514 1404 393
Answer:
B, E
Step-by-step explanation:
The ratios of side lengths in a 30-60-90 triangle are ...
1 : √3 : 2
The two legs are the shorter sides, so any ratio that reduces to 1 : √3 is an appropriate choice:
B. 1 : √3
E. 2√3 : 6
Have you got your answer yet?
Answer:
Step-by-step explanation:
The student hasn't finished the factoring yet.
<u>He still needs the step:</u>
<u>The next step:</u>
- 0 = 2x + 5, 0 = x + 1
- x = - 2.5, x = - 1
