Find dy/dx by implicit differentiation. x2 − 4xy + y2 = 4

Plz help me with the ones that are circled

Alisiya [41]

Your answer for your question is going to be.... um.... sorry I forgot

3 0

3 years ago

The temperature changed from 7°f at 6pm to -5°f at midnight. What was the difference between the high an low temperatures? Whats

Ronch [10]

Answer:

Difference between high and low temperatures: 12°F

Average change in temperature per hour: 2°F

Step-by-step explanation:

The difference between high and low temperatures was: 7 - (-5) = 12 (°F)

Midnight is 12am, so 6pm to midnight is 6 hours.

The average change in temperature per hour is: 12 / 6 = 2 (°F)

7 0

3 years ago

In a recent year, a sample of grade 8 Washington State public school students taking a mathematics assessment test had a mean sc

Daniel [21]

Answer:

The number is $N =1147$ students

Step-by-step explanation:

From the question we are told that

The population mean is $\mu = 281$

The standard deviation is $\sigma = 34.4$

The sample size is n = 2000

percentage of the would you expect to have a score between 250 and 305 is mathematically represented as

$P(250 < X < 305 ) = P(\frac{ 250 - 281}{34.4 } < \frac{X - \mu }{\sigma } < \frac{ 305 - 281}{34.4 } )$

Generally

$\frac{X - \mu }{\sigma } = Z (Standardized \ value \ of \ X )$

So

$P(250 < X < 305 ) = P(-0.9012< Z$

$P(250 < X < 305 ) = P(z_2 < 0.698 ) - P(z_1 < -0.9012)$

From the z table the value of $P( z_2 < 0.698) = 0.75741$

and $P(z_1 < -0.9012) = 0.18374$

$P(250 < X < 305 ) = 0.75741 - 0.18374$

$P(250 < X < 305 ) = 0.57$

The percentage is $P(250 < X < 305 ) = 57\%$

The number of students that will get this score is

$N = 2000 * 0.57$

$N =1147$

6 0

3 years ago

Your sister is getting married this summer and she has asked you to help her select a D.J.

ioda

So Dave charges 150 at first and then 10.50 per each hour, so if your sister has the party going for say "h" hours, then his total charges will then be 150 + 10.5h.

now, Marvin's Mobile Music charges 135 at first, but then is more expensive per hour is 15 bucks per each hour, so if she has a party for "h" hours, then his total charges are 135 + 15h.

now, let's check when they're both equal, at how many hours will they cost your sister the same amount.

$\bf 150+10.50h=135+15h\implies 150-135=15h-10.5h
\\\\\\
15=4.5h\implies 15=4\frac{1}{2}h\implies 15=\cfrac{9}{2}h\implies \cfrac{15}{\frac{9}{2}}=h\implies \cfrac{\frac{15}{1}}{\frac{9}{2}}=h
\\\\\\
\cfrac{15}{1}\cdot \cfrac{2}{9}=h\implies \cfrac{30}{9}=h\implies \cfrac{10}{3}=h\implies 3\frac{1}{3}=h$

so, 3 and a third of a hour, or 3 hours and 20 minutes, they both will cost your sister the same amount, so it wouldn't matter who's hired if the party is only 3 hours and 20 minutes long.

however, after that, the one with higher hourly rate, Marvin's, gets more expensive, and she's better off hiring the one with cheaper hourly rate.

now, you can just get some mp3s and some loud speakers and nevermind the DJs and you do it, or she can do it, I have the macarena song if you need that one.

3 0

3 years ago

The pair of values below is from a direct variation. Find the missing number.

NISA [10]

Answer:

The answer is 2.

2 since 6/4=3/2

Step-by-step explanation:

Since your relation is a direct variation then the points on your line are of the form y=kx where k is the constant of variation (also called constant of proportionality)

If y=kx then y/x=k.

So all the points in this relation since it is a direct variation will be equal to y-coordinate/x-coordinate.

So we are going to solve this proportion:

$\frac{6}{4}=\farc{3}{x}$