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
Step2247 [10]
3 years ago
7

If y varies directly as x, and y is 20 when x is 4, whats this relation?

Mathematics
1 answer:
nignag [31]3 years ago
7 0
Y α x

y = kx

20 = k*4

20 = 4k

20/4 = k

5 = k

k = 5

Relation is y = kx ,  that is    y = 5x
You might be interested in
Jack has $24 in one-dollar and five- dollar bills. He has a total of 8 bills. How many of each bill does he have?​
mylen [45]
He has 4 $5 bills and 4 $1 bills
3 0
2 years ago
Read 2 more answers
Litter such as leaves falls to the forest floor, where the action of insects and bacteria initiates the decay process. Let A be
Travka [436]

Answer:

D = L/k

Step-by-step explanation:

Since A represents the amount of litter present in grams per square meter as a function of time in years, the net rate of litter present is

dA/dt = in flow - out flow

Since litter falls at a constant rate of L  grams per square meter per year, in flow = L

Since litter decays at a constant proportional rate of k per year, the total amount of litter decay per square meter per year is A × k = Ak = out flow

So,

dA/dt = in flow - out flow

dA/dt = L - Ak

Separating the variables, we have

dA/(L - Ak) = dt

Integrating, we have

∫-kdA/-k(L - Ak) = ∫dt

1/k∫-kdA/(L - Ak) = ∫dt

1/k㏑(L - Ak) = t + C

㏑(L - Ak) = kt + kC

㏑(L - Ak) = kt + C'      (C' = kC)

taking exponents of both sides, we have

L - Ak = e^{kt + C'} \\L - Ak = e^{kt}e^{C'}\\L - Ak = C"e^{kt}      (C" = e^{C'} )\\Ak = L - C"e^{kt}\\A = \frac{L}{k}  - \frac{C"}{k} e^{kt}

When t = 0, A(0) = 0 (since the forest floor is initially clear)

A = \frac{L}{k}  - \frac{C"}{k} e^{kt}\\0 = \frac{L}{k}  - \frac{C"}{k} e^{k0}\\0 = \frac{L}{k}  - \frac{C"}{k} e^{0}\\\frac{L}{k}  = \frac{C"}{k} \\C" = L

A = \frac{L}{k}  - \frac{L}{k} e^{kt}

So, D = R - A =

D = \frac{L}{k} - \frac{L}{k}  - \frac{L}{k} e^{kt}\\D = \frac{L}{k} e^{kt}

when t = 0(at initial time), the initial value of D =

D = \frac{L}{k} e^{kt}\\D = \frac{L}{k} e^{k0}\\D = \frac{L}{k} e^{0}\\D = \frac{L}{k}

4 0
2 years ago
10 in<br> Given the figure. Find AC.
rjkz [21]

Answer:

if its an arc and center angle is given it could be double the size. IF it is a triangle measure you would use Pythagoras for triangle and trig for given angle, if two triangles are shown and they are scale of each other alternative measures given divide into each measure by the correct line and check this with the matching angles. when found as a division this is the ratio so then you just multiply to find the larger measure but divide to find the smaller measure. AC could also be a junction or vector, if its a type of vector then you just follow the arrows and count how many arrows fit the line pick a direction and ie) if its x2 a then you show a+a.

Step-by-step explanation:

5 0
3 years ago
Round to the nearest ten-thousand <br> 568,135
DIA [1.3K]

Answer:

Step-by-step explanation:

570000 to the nearest ten thousand

6 0
2 years ago
Find the surface area and volume of the prism
Zigmanuir [339]

Answer:

Step-by-step explanation:

5 0
2 years ago
Other questions:
  • A rainstorm in Portland, Oregon, has wiped out the electricity in about 5% of the households in the city. A management team in P
    11·1 answer
  • A car salesman earns a base salary plus commission for every car he sells. The expression shows the amount the salesperson earns
    13·2 answers
  • Sally has already read 200 pages of her book. She plans to read 10 pages each day until she finishes. Write an equation of pages
    7·1 answer
  • Variable c is 5 more than variable
    6·2 answers
  • 2/3 - 4x + 7/2 = -9x + 5/6 apply the properties.. step by step
    12·2 answers
  • Linda earns $5.25 and spent $3.75 one week the next week she earned $4.40 and spent $2.25 how much money did Linda have left aft
    12·1 answer
  • PLS HELPPP Jamal has the following choices for his pizza: white sauce or red sauce; white cheese or yellow cheese; and mushrooms
    11·2 answers
  • What is the value of x when g(h(x)) = 4?
    14·1 answer
  • PLS HELPPP MEEE ILL GIVE BRAINLIEST
    6·2 answers
  • What fraction is represented by point A on the number line shown?
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!