1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
tankabanditka [31]
3 years ago
11

The feet of a commemorative parabolic steel arch 100m high are 200m apart. Determine whether the focus of the arch is above or b

elow ground and indicate the number of feet it lies above or below ground.
75 ft above

25 ft above

25 ft below

75 ft below
Mathematics
2 answers:
Citrus2011 [14]3 years ago
8 0
The focus of the arch is 75 ft. above ground
Neko [114]3 years ago
7 0
<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>
You might be interested in
The water was pumped out of a backyard pond. What is the domainof this graph?
nalin [4]
I think it's D because you can't have negative minutes and after 8 minutes you can't go any deeper than 0 inches.
8 0
3 years ago
Emily needs enough Fabric for 3 1/2 hats. Since she has half a hat done. If each bag requires 1 2/7 ft of Fabric, how much fabri
kow [346]

first off let's convert the mixed fractions to improper fractions.

\stackrel{mixed}{3\frac{1}{2}}\implies \cfrac{3\cdot 2+1}{2}\implies \stackrel{improper}{\cfrac{7}{2}} ~\hfill \stackrel{mixed}{1\frac{2}{7}}\implies \cfrac{1\cdot 7+2}{7}\implies \stackrel{improper}{\cfrac{9}{7}}

she already did half a hat, so we can say   \cfrac{7}{2}-\cfrac{1}{2}\implies \cfrac{7-1}{2}\implies 3

so she only needs enough fabric to make 3 more full hats, we know each one uses 9/7 ft, so

3\cdot \cfrac{9}{7}\implies \cfrac{27}{7}\implies 3\frac{6}{7}

5 0
2 years ago
Rewrite the fraction in the sentence below as a percentage. In 2002, a popular company made 11/20 of its money online.​
Vladimir79 [104]

Answer:

55%

Step-by-step explanation:

11/20 = 0.55

0.55 = 55%

7 0
2 years ago
A large truck has two fuel tanks, each with a capacity of 150 gallons. Tank 1 is half full, and Tank 2 is empty.
12345 [234]

Answer:

1) G(t) = 75 + \frac{23}{4}t\\

2) After 8 minutes delivering fuel the tanks will have 121 gallons of fuel

Step-by-step explanation:

1) For generating the equation we have to take into account that in the tanks there is a initial volume of fuel that corresponds to 75 gallons, as it is stated that tank one is half full. As the capacity for tank 1 is of 150 gallons, half of the tank equals to:

\frac{150}{2} = 75 gallons

Now we have to convert the rate of delivery that is expressed as a mixed number to an improper fraction so:

5\frac{3}{4} = \frac{(5x4)+3}{4} = \frac{23}{4}

Then the pumping rate is of 23/4 gallons per minute, to get how many gallons are in the tank we just need to multiply this rate by the time in minutes, and as there is an initial volume we have to add it, so we have the following equation:

G(t) = 75 + \frac{23}{4}t\\

2) To know how much fuel is in the tank after 8 minutes we have to replace this time in the previous equation so we have

G(t) = 75 + \frac{23}{4}t\\G(8) = 75 + \frac{23}{4}(8)\\G(8) = 75 + 23(2)\\G(8) = 75 + 46\\G(8) = 121 gallons

After 8 minutes delivering fuel the tanks will have 121 gallons of fuel

8 0
3 years ago
Calculate the surface​
ludmilkaskok [199]

Answer:

What is the surface

Step-by-step explanation:

U should put a pic or something so we can help u <3 btw can u give me a brainllest cuz i need 1 more to hit 5 thank u <3

7 0
3 years ago
Other questions:
  • The table of values shows the output values of three different equations for the same
    5·1 answer
  • CAN SOME ONE HELP ME WITH THIS HURRY PLEASE
    7·1 answer
  • convert the measurement 5,000 yards (There are 1.09 yards in a meter.) A. 4000 m B. 6000 m C. 5 km D. 500 m
    14·1 answer
  • To convert 10 minutes to seconds, you would use the ratio. 1 seconds/ 60 mins
    14·2 answers
  • Verify sin^4 x - sin^2 x = cos^4 x - cos^2 x is an identity
    5·1 answer
  • Find the unknown sides and angles of this triangle using the Law of Cosines.
    8·1 answer
  • What is the quotient of 15,048 and 76​
    11·1 answer
  • HELP?????????????????????/
    11·2 answers
  • What is the greatest common factor (GCF) of 64 and 48?
    6·2 answers
  • Help please and explain this for me please thanks
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!