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What might a scatterplot of data points look like if it were best described by a logarithmic model?

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What does the y -intercept on the graph of a logistic equation correspond to for a population modeled by that equation?

The y -intercept on the graph of a logistic equation corresponds to the initial population for the population model.

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Graphical

For the following exercises, match the given function of best fit with the appropriate scatterplot in [link] through [link] . Answer using the letter beneath the matching graph.

Graph of a scattered plot.
Graph of a scattered plot.
Graph of a scattered plot.
Graph of a scattered plot.
Graph of a scattered plot.

y = 10.209 e 0.294 x

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y = 5.598 1.912 ln ( x )

C

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y = 4.607 + 2.733 ln ( x )

B

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y = 14.005 1 + 2.79 e 0.812 x

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Numeric

To the nearest whole number, what is the initial value of a population modeled by the logistic equation P ( t ) = 175 1 + 6.995 e 0.68 t ? What is the carrying capacity?

P ( 0 ) = 22 ; 175

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Rewrite the exponential model A ( t ) = 1550 ( 1.085 ) x as an equivalent model with base e . Express the exponent to four significant digits.

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A logarithmic model is given by the equation h ( p ) = 67.682 5.792 ln ( p ) . To the nearest hundredth, for what value of p does h ( p ) = 62 ?

p 2.67

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A logistic model is given by the equation P ( t ) = 90 1 + 5 e 0.42 t . To the nearest hundredth, for what value of t does P ( t ) = 45 ?

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What is the y -intercept on the graph of the logistic model given in the previous exercise?

y -intercept: ( 0 , 15 )

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Technology

For the following exercises, use this scenario: The population P of a koi pond over x months is modeled by the function P ( x ) = 68 1 + 16 e 0.28 x .

Graph the population model to show the population over a span of 3 years.

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What was the initial population of koi?

4 koi

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How many koi will the pond have after one and a half years?

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How many months will it take before there are 20 koi in the pond?

about 6.8 months.

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Use the intersect feature to approximate the number of months it will take before the population of the pond reaches half its carrying capacity.

Graph of the intersection of P(t)=68/(1+16e^(-0.28t)) and y=34.
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For the following exercises, use this scenario: The population P of an endangered species habitat for wolves is modeled by the function P ( x ) = 558 1 + 54.8 e 0.462 x , where x is given in years.

Graph the population model to show the population over a span of 10 years.

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What was the initial population of wolves transported to the habitat?

10 wolves

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How many wolves will the habitat have after 3 years?

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How many years will it take before there are 100 wolves in the habitat?

about 5.4 years.

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Use the intersect feature to approximate the number of years it will take before the population of the habitat reaches half its carrying capacity.

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For the following exercises, refer to [link] .

x f(x)
1 1125
2 1495
3 2310
4 3294
5 4650
6 6361

Use a graphing calculator to create a scatter diagram of the data.

Graph of the table’s values.
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Use the regression feature to find an exponential function that best fits the data in the table.

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Write the exponential function as an exponential equation with base e .

f ( x ) = 776.682 e 0.3549 x

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Graph the exponential equation on the scatter diagram.

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Use the intersect feature to find the value of x for which f ( x ) = 4000.

When f ( x ) = 4000 , x 4.6.

Graph of the intersection of a scattered plot with an estimation line and y=4,000.
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For the following exercises, refer to [link] .

x f(x)
1 555
2 383
3 307
4 210
5 158
6 122

Use a graphing calculator to create a scatter diagram of the data.

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Questions & Answers

how did you get 1640
Noor Reply
If auger is pair are the roots of equation x2+5x-3=0
Peter Reply
Wayne and Dennis like to ride the bike path from Riverside Park to the beach. Dennis’s speed is seven miles per hour faster than Wayne’s speed, so it takes Wayne 2 hours to ride to the beach while it takes Dennis 1.5 hours for the ride. Find the speed of both bikers.
MATTHEW Reply
420
Sharon
from theory: distance [miles] = speed [mph] × time [hours] info #1 speed_Dennis × 1.5 = speed_Wayne × 2 => speed_Wayne = 0.75 × speed_Dennis (i) info #2 speed_Dennis = speed_Wayne + 7 [mph] (ii) use (i) in (ii) => [...] speed_Dennis = 28 mph speed_Wayne = 21 mph
George
Let W be Wayne's speed in miles per hour and D be Dennis's speed in miles per hour. We know that W + 7 = D and W * 2 = D * 1.5. Substituting the first equation into the second: W * 2 = (W + 7) * 1.5 W * 2 = W * 1.5 + 7 * 1.5 0.5 * W = 7 * 1.5 W = 7 * 3 or 21 W is 21 D = W + 7 D = 21 + 7 D = 28
Salma
Devon is 32 32​​ years older than his son, Milan. The sum of both their ages is 54 54​. Using the variables d d​ and m m​ to represent the ages of Devon and Milan, respectively, write a system of equations to describe this situation. Enter the equations below, separated by a comma.
Aaron Reply
find product (-6m+6) ( 3m²+4m-3)
SIMRAN Reply
-42m²+60m-18
Salma
what is the solution
bill
how did you arrive at this answer?
bill
-24m+3+3mÁ^2
Susan
i really want to learn
Amira
I only got 42 the rest i don't know how to solve it. Please i need help from anyone to help me improve my solving mathematics please
Amira
Hw did u arrive to this answer.
Aphelele
hi
Bajemah
-6m(3mA²+4m-3)+6(3mA²+4m-3) =-18m²A²-24m²+18m+18mA²+24m-18 Rearrange like items -18m²A²-24m²+42m+18A²-18
Salma
complete the table of valuesfor each given equatio then graph. 1.x+2y=3
Jovelyn Reply
x=3-2y
Salma
y=x+3/2
Salma
Hi
Enock
given that (7x-5):(2+4x)=8:7find the value of x
Nandala
3x-12y=18
Kelvin
please why isn't that the 0is in ten thousand place
Grace Reply
please why is it that the 0is in the place of ten thousand
Grace
Send the example to me here and let me see
Stephen
A meditation garden is in the shape of a right triangle, with one leg 7 feet. The length of the hypotenuse is one more than the length of one of the other legs. Find the lengths of the hypotenuse and the other leg
Marry Reply
how far
Abubakar
cool u
Enock
state in which quadrant or on which axis each of the following angles given measure. in standard position would lie 89°
Abegail Reply
hello
BenJay
hi
Method
I am eliacin, I need your help in maths
Rood
how can I help
Sir
hmm can we speak here?
Amoon
however, may I ask you some questions about Algarba?
Amoon
hi
Enock
what the last part of the problem mean?
Roger
The Jones family took a 15 mile canoe ride down the Indian River in three hours. After lunch, the return trip back up the river took five hours. Find the rate, in mph, of the canoe in still water and the rate of the current.
cameron Reply
Shakir works at a computer store. His weekly pay will be either a fixed amount, $925, or $500 plus 12% of his total sales. How much should his total sales be for his variable pay option to exceed the fixed amount of $925.
mahnoor Reply
I'm guessing, but it's somewhere around $4335.00 I think
Lewis
12% of sales will need to exceed 925 - 500, or 425 to exceed fixed amount option. What amount of sales does that equal? 425 ÷ (12÷100) = 3541.67. So the answer is sales greater than 3541.67. Check: Sales = 3542 Commission 12%=425.04 Pay = 500 + 425.04 = 925.04. 925.04 > 925.00
Munster
difference between rational and irrational numbers
Arundhati Reply
When traveling to Great Britain, Bethany exchanged $602 US dollars into £515 British pounds. How many pounds did she receive for each US dollar?
Jakoiya Reply
how to reduced echelon form
Solomon Reply
Jazmine trained for 3 hours on Saturday. She ran 8 miles and then biked 24 miles. Her biking speed is 4 mph faster than her running speed. What is her running speed?
Zack Reply
d=r×t the equation would be 8/r+24/r+4=3 worked out
Sheirtina
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Source:  OpenStax, Precalculus. OpenStax CNX. Jan 19, 2016 Download for free at https://legacy.cnx.org/content/col11667/1.6
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