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anonymous
 one year ago
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anonymous
 one year ago
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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0The number of fish (F) in a fish tank increases when the number of plants (P) increases. Write the correct equation for this scenario, and solve for the number of fish when the number of plants is 3. Plants Fish 15 6 20 8 F = P; F = 3 F = .4P; F = 1.2 F = 90 over P; F = 30 F = 90 over P; F = 270

phi
 one year ago
Best ResponseYou've already chosen the best response.2you could think of Plants as x and Fish as y then you have the two points (15,6) and (20,8) do you know how to find the equation of a line through 2 points?

phi
 one year ago
Best ResponseYou've already chosen the best response.2the first step is find the slope which is change in y divided by change in x

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0\[\frac{ 8  6 }{ 20 15 } = \frac{ 2 }{ 5 } \]

phi
 one year ago
Best ResponseYou've already chosen the best response.2yes. now write down the equation y = m x + b you found m is 2/5 so you know \[ y = \frac{2}{5} x + b \] replace y and x with the values from one of the points for example, use (15,6) i.e. let x=15 and y=6 then find b can you do that ?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0yup. \[6 = \frac{ 2 }{ 5 }(15) + b\] then \[6 = 6 + b \] to get \[0=b\] so \[b = 0\]

phi
 one year ago
Best ResponseYou've already chosen the best response.2yes, so the equation becomes \[ y = \frac{2}{5} x \] (adding b=0 is not necessary) or, renaming x and y back to plants and fishes i.e. use P and F: \[ F= \frac{2}{5} P\]

phi
 one year ago
Best ResponseYou've already chosen the best response.2is that enough to answer the question ?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0idk im not sure what to do next

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so do i plug in 3 for plants

phi
 one year ago
Best ResponseYou've already chosen the best response.2you can do that. what do you get ?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.01.2 so its B because 2/5 = .4

phi
 one year ago
Best ResponseYou've already chosen the best response.2yes, and notice that 2/5 is the same a 0.4 so we could write the equation as y = 0.4 x or F= 0.4 P

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0thnk you so much i have more can you help w/?

phi
 one year ago
Best ResponseYou've already chosen the best response.2notice that once you realize that 2/5 is 0.4 then F= 0.4 P means only choice B works. (all the other choices have the wrong equation)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Rae earns $60 for playing music on Saturday nights at the local coffee house. She makes an average of $5.25 in tips per hour. Write the function of Rae's earnings, and solve for how much she would make after 4 hours. y = 5.25x + 60; $65.25 y = 60x + 5.25; $85.75 y = 5.25x + 60; $81.00 y = 60x + 5.25; $185.25

phi
 one year ago
Best ResponseYou've already chosen the best response.2any thought on what x and y represent in this problem ?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0y = hour and the tip is x?

phi
 one year ago
Best ResponseYou've already chosen the best response.2look at this sentence: how much she would make after 4 hours ? what do they want us to calculate? I would say "how much she makes" i.e. earnings. what do we "use" to figure out the earnings? the number of hours so you should think y (I want to know this ) equals stuff with an x (put in x and do some arithmetic)

phi
 one year ago
Best ResponseYou've already chosen the best response.2next, what in the problem goes with "number of hours". we read this $5.25 in tips per hour. that means to figure out how much in tips we need to know how many hours she worked (she get 5.25 for each hour)

phi
 one year ago
Best ResponseYou've already chosen the best response.2ok, can you write what you think y and x stand for ?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0im not sure this one is really confusing

phi
 one year ago
Best ResponseYou've already chosen the best response.2we want to write down an equation that lets us calculate how much she made we would write y = something and y is what we are trying to calculate

phi
 one year ago
Best ResponseYou've already chosen the best response.2if she got no tips, how much are her earnings? Based on what they tell you.

phi
 one year ago
Best ResponseYou've already chosen the best response.2and if you write it as an equation y= 60

phi
 one year ago
Best ResponseYou've already chosen the best response.2now add in how much she makes in tips. can you do that ?

phi
 one year ago
Best ResponseYou've already chosen the best response.2pretty close. even better. and yes, bingo!

phi
 one year ago
Best ResponseYou've already chosen the best response.2now use x=4 to find how much she made

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0y = 5.25(4) + 60 so y = 21 + 60 equals y = 81

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0What is the slope of the line that passes through (2, 5) and (−1, 5)? −3 0 < my choice Undefined 3

phi
 one year ago
Best ResponseYou've already chosen the best response.2yes (55)/(12) = 0/(3) = 0

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0The function for the cost of materials to make a muffin is f(x) = Three fourths x + 3, where x is the number of muffins. The function for the selling price of those muffins is g(f(x)), where g(x) = 3x + 4. Find the selling price of 20 muffins. 18 49 51 58 < my choice

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Below are two different functions, f(x) and g(x). What can be determined about their slopes? f(x) Dawn writes 800 pages in 80 days. x g(x) 2 −6 4 12 6 30 The function f(x) has a larger slope. The function g(x) has a larger slope. They both have the same slope. The relationship between slopes cannot be determined. idk this one

phi
 one year ago
Best ResponseYou've already chosen the best response.2can you find the slope for g(x) (think of g(x) as "y") ?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0\[\frac{ 30  12 }{ 6 4 } = \frac{ 18 }{ 2 } = 9\]

phi
 one year ago
Best ResponseYou've already chosen the best response.2and if we want to be sure, check another (x,y) pair (in case they are being tricky) (12 6) / (42) = 18/2 = 9 good , we get the same slope (which means g(x) is a straight line)

phi
 one year ago
Best ResponseYou've already chosen the best response.2the 800 pages in 80 days means 800/80 = 10 pages per day when you see a "rate" (or the "per" word) , you can think of that as a slope.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so the function f(x) has a large slope

phi
 one year ago
Best ResponseYou've already chosen the best response.2for example, if you remember the "tip" problem, you were told 5.25 per hour (the per was a clue that the 5.25 is a slope that multiplies x)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Below are two different functions, f(x) and g(x). What can be determined about their slopes? f(x) = 2x + 3 The function g(x) going through 1 on the x axis and 1, 4 The function f(x) has a larger slope. < my choice The function g(x) has a larger slope. They both have the same slope. The relationship between slopes cannot be determined.

phi
 one year ago
Best ResponseYou've already chosen the best response.2what is the change in y divided by change in x for g(x) ?

phi
 one year ago
Best ResponseYou've already chosen the best response.2notice the change in x is 0 and we get change in y divided by 0 which technically is not defined, but we can think of as approaching infinity I hope they are not being tricky... but I would say the slope of g(x) is *very large*

phi
 one year ago
Best ResponseYou've already chosen the best response.2it might be, but I would go with with g(x) slope is larger than f(x)

phi
 one year ago
Best ResponseYou've already chosen the best response.2but no guarantees on that one.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0ill check with someone else later but thnx

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0jorge was tracking the decreasing temperature in the morning. At 7 a.m., it was 65 degrees Fahrenheit. At 9 a.m., it was 55 degrees Fahrenheit. If Jorge made the function f(x) = −5x + 100, what would the −5 represent? The temperature at midnight The length of time he recorded for The total change in degrees The rate at which the temperature was decreasing

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0thnx i got only 2 more

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0The number of roses (r) in a garden increases when the number of weeds (w) decreases. Write the correct equation for this scenario, and solve for the number of roses when there are 5 weeds. Weeds Roses 10 20 20 10 r = 200 over w; r = 40 r = 200 over w; r = 1000 r = 2w; r = 10 r = 2w; r = 2.5

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0this is similar to the one with the plants and it was like.4

phi
 one year ago
Best ResponseYou've already chosen the best response.2it might not be a line with this one.

phi
 one year ago
Best ResponseYou've already chosen the best response.2if we assume a straight line through the two points (10,20) and (20,10) we get y= x +30 or r =  w + 30 and none of your choices have that equation

phi
 one year ago
Best ResponseYou've already chosen the best response.2but it sounds like "inverse variation" in other words \[ y = \frac{k}{x} \]

phi
 one year ago
Best ResponseYou've already chosen the best response.2use an (x,y) pair to "solve for k" or in this case \[ r = \frac{k}{w} \] use a (w,r) pair

phi
 one year ago
Best ResponseYou've already chosen the best response.2in other words, use (20,10) i.e. w=20, r=10 in that equation and simplify to find k

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0\[10 = \frac{ k }{ 20 } \] \[20 * 10 = k \] \[k = 200\]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0\[r = \frac{ 200 }{ w }\]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Below are two different functions, f(x) and g(x). What can be determined about their yintercepts? graph going through 3, 2 and 3, 4 x g(x) 2 1 4 3 6 5 The function f(x) has a higher yintercept. The function g(x) has a higher yintercept. They both have the same yintercept. The relationship between yintercepts cannot be determined.

phi
 one year ago
Best ResponseYou've already chosen the best response.2f(x) is a vertical line and does not have a yintercept. so cannot be determined. (maybe you should choose cannot be determined for the other question about a vertical line)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0okay ill ask someone else thnx
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