Solve this equation: please show all the work<br><br> <img src="https://tex.z-dn.net/?f=x%5E%7B3%7D-y%2B9-%28xy%29" id="TexFormu

When y=-2, what kind of line does it have horizontal or vertical

Rashid [163]

Answer: Horizontal

Step-by-step explanation: The equation <em>y = -2</em> can be thought of as y = 0x - 2. So our line has a slope of 0 and a y-intercept of -2.

To graph it, we start with the y-intercept, down 2 units on the y-axis. Now, if the slope of a line is 0, then the line must be flat or horizontal.

So we just draw a horizontal line through the y-intercept of -2.

In fact, when the equation of any line reads y = a number, it's graph will always be a horizontal line. For example, y = 3, y = -10, y = -8 and so on.

Image provided below.

8 0

3 years ago

Let X denote the length of human pregnancies from conception to birth, where X has a normal distribution with mean of 264 days a

Kaylis [27]

Answer:

Step-by-step explanation:

Hello!

X: length of human pregnancies from conception to birth.

X~N(μ;σ²)

μ= 264 day

σ= 16 day

If the variable of interest has a normal distribution, it's the sample mean, that it is also a variable on its own, has a normal distribution with parameters:

X[bar] ~N(μ;σ²/n)

When calculating a probability of a value of "X" happening it corresponds to use the standard normal: Z= (X[bar]-μ)/σ

When calculating the probability of the sample mean taking a given value, the variance is divided by the sample size. The standard normal distribution to use is Z= (X[bar]-μ)/(σ/√n)

a. You need to calculate the probability that the sample mean will be less than 260 for a random sample of 15 women.

P(X[bar]<260)= P(Z<(260-264)/(16/√15))= P(Z<-0.97)= 0.16602

b. P(X[bar]>b)= 0.05

You need to find the value of X[bar] that has above it 5% of the distribution and 95% below.

P(X[bar]≤b)= 0.95

P(Z≤(b-μ)/(σ/√n))= 0.95

The value of Z that accumulates 0.95 of probability is Z= 1.648

Now we reverse the standardization to reach the value of pregnancy length:

1.648= (b-264)/(16/√15)

1.648*(16/√15)= b-264

b= [1.648*(16/√15)]+264

b= 270.81 days

c. Now the sample taken is of 7 women and you need to calculate the probability of the sample mean of the length of pregnancy lies between 1800 and 1900 days.

Symbolically:

P(1800≤X[bar]≤1900) = P(X[bar]≤1900) - P(X[bar]≤1800)

P(Z≤(1900-264)/(16/√7)) - P(Z≤(1800-264)/(16/√7))

P(Z≤270.53) - P(Z≤253.99)= 1 - 1 = 0

d. P(X[bar]>270)= 0.1151

P(Z>(270-264)/(16/√n))= 0.1151

P(Z≤(270-264)/(16/√n))= 1 - 0.1151

P(Z≤6/(16/√n))= 0.8849

With the information of the cumulated probability you can reach the value of Z and clear the sample size needed:

P(Z≤1.200)= 0.8849

$Z= \frac{X[bar]-Mu}{Sigma/\sqrt{n} }$

$Z*(Sigma/\sqrt{n} )= (X[bar]-Mu)$

$(Sigma/\sqrt{n} )= \frac{(X[bar]-Mu)}{Z}$

$Sigma= \frac{(X[bar]-Mu)}{Z}*\sqrt{n}$

$Sigma*(\frac{Z}{(X[bar]-Mu)})= \sqrt{n}$

$n = (Sigma*(\frac{Z}{(X[bar]-Mu)}))^2$

$n = (16*(\frac{1.2}{(270-264)}))^2$

n= 10.24 ≅ 11 pregnant women.

I hope it helps!

6 0

2 years ago

The length of each side is quadrupled. How many times larger is the new area when compared to the original?

GaryK [48]

16 times larger is the new area when compared to the original.

Given that, the length of each side of the square is quadrupled.

We need to find how many times larger is the new area when compared to the original.

<h3>What is the area of a square?</h3>

A square is a closed two-dimensional shape with four equal sides and four equal angles. The four sides of the square form the four angles at the vertices. The sum of the total length of the sides of a square is its perimeter, and the total space occupied by the shape is the area of the square. The formula to calculate the area of a square is a².

Let the length of each side of the square be x.

Then the length of each side of the new square will be 4x.

Now, the area of the original square = x²

The area of the new square = (4x)² = 16x²

So, the new square = 16 × the original square

Therefore, 16 times larger is the new area when compared to the original.

To learn more about the area of a square visit:

brainly.com/question/1561162.

#SPJ1

5 0

1 year ago

What is the value for x in the diagram? Rounded to the nearest whole<br> degree.

AnnZ [28]

Answer:

49

Step-by-step explanation:

cos(x)=31/47

x=cos^-1 (31/47)

8 0

3 years ago

Read 2 more answers

If w= the weight of a trout, which algebraic expression represents the phrase

RoseWind [281]

Answer:

it would be w7

Step-by-step explanation:

because to get w you mulitply w with 7

so all that you need to do is put the 7 next to the w

because mathematicians are known to be lazzy so they do not put the multiplication sign, instead the put it next to each other meaning that it is mulitplied

simple awnser for the simple question

6 0

2 years ago