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
nadezda [96]
3 years ago
8

A building has an entry the shape of a parabolic arch 84 ft high and 42 ft wide at the base, as shown below. A parabola opening

down with vertex at the origin is graphed on the coordinate plane. The height of the parabola from top to bottom is 84 feet and its width from left to right is 42 feet. Find an equation for the parabola if the vertex is put at the origin of the coordinate system. (
Mathematics
2 answers:
Grace [21]3 years ago
6 0

Answer:

x² = -21y

Step-by-step explanation:

THIS IS THE RIGHT ANSWER I TOOK THE TEST

lara [203]3 years ago
3 0

Answer:

Step-by-step explanation:

Because of the nature of the information we are given, we have no choice but to use the equation

y=a(x-h)^2+k

and solve for a.

We know by the info that the vertex is (0, 84). We also know that if the vertex is at the origin, and that the base is 42 feet wide, it spans 21 feet to the right of the origin and 21 feet to the left of the origin. That means that we have 2 coordinates from which we need to pick one for our x and y in the equation. I don't like negatives, so I am going to choose the coordinate (21, 0) as x and y. Because this parabola opens upside down, as archways of door openings do, our "a" value better come out algebraically as a negative. Let's see...From the vertex we have that h = 0 and k = 84. So filling in:

0=a(21-0)^2+84 and simplifying a bit:

0 = 441a + 84 and

-84 = 441a so

a=-\frac{84}{441}=-\frac{4}{21} Good, a is negative. Your equation is, then:

y=-\frac{4}{21}x^2+84

You might be interested in
What are the values of a and b? Select one: a. a equals 18 comma space b equals 4 square root of 5 b. a equals 64 comma space b
OleMash [197]

Answer:

a is a value of 5 and b is is equal to 9

Step-by-step explanation:

all you have to do is get 16 and 4 by them self and take them out, and find the remaining numbers

3 0
3 years ago
There are 19 boxes of cherries. This is 5 less than twice the number of boxes of kiwis. How many boxes of kiwis are there?
sasho [114]
All you have to do is 19+5 because it is 5 less. 19 is 5 less than the kiwis. so 19+5= 24.  


There is 24 boxes of kiwis
8 0
3 years ago
Read 2 more answers
Which of the following polynomials is in standard form?
NNADVOKAT [17]

Answer:

A

B

C

Step-by-step explanation:

4 0
3 years ago
Read 2 more answers
What is the area of the figure? <br> A. 66 <br> B. 84 <br> C. 60 <br> D. 72
Lerok [7]

Answer:

C.60

Step-by-step explanation:

4×12=48

18-12=6

6×2=12

48+12=60

3 0
3 years ago
Read 2 more answers
What is the answer for number 6
Ilya [14]
Inches: 2 4 6 8 1 21
centimeters: 8 10 12 14 7
6 0
3 years ago
Read 2 more answers
Other questions:
  • If bethany earned $51,740 last year, how much did she earn per week?
    10·1 answer
  • What is 4 1/3 + (5+6 2/3) ?
    5·2 answers
  • Solve for m 35m=7 simplify your answer as much as possible
    6·1 answer
  • HELP ASAP PLEASE!!!!!!!!!!!!Factor completely 8x^2 - 4x – 84.
    14·1 answer
  • What is the slope of the line given by the equation y = 3x? enter your answer as an integer.
    6·1 answer
  • Last week, Lisa drove 12 meters to visit her uncle. Is it meters, centimeters, kilometers, or millimeters?
    12·1 answer
  • Two sons shared ₦14,000 in the ratio of 4 ratio 3 what are their respective shares<br>​
    6·1 answer
  • After swimming to a depth of 55 feet below the surface of
    8·1 answer
  • Nikos, a 39-year old male, bought a 300,000, 20-year life insurance policy.
    14·1 answer
  • The method of least squares of residuals is commonly used to get the best fit with linear regression. The reason why the absolut
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!