Question
Consider this system of equations. Which shows the second equation written in slope-intercept form?


A. 
B. 
C. 
D. 
Answer:
B. 
Step-by-step explanation:
Given
Equation 1: 
Equation 2: 
Required:
Equivalent of equation 2
To get an equivalent of equation 2 (in slope intercept form), first we have to simplify equation 2

Open the bracket


Simplify fraction

Divide through by 2


Re-arrange

The next step is to compare each of option A through D with 
A.
is not equal to 
We check the next available option
B.
is equal to 
This option is equivalent to the second equation in slope-intercept form.
We check further if there are more equivalent options
C.

Convert fraction to decimal

This is not equal to 
D.

Convert fraction to decimal

This is not equal to 
Hence, the only equation that is equivalent to the second equation written in slope intercept form is Option B
Answer:
a)Slope:
Intercept:
b)
And the determination coeffecient is
Step-by-step explanation:
Data given and definitions
The correlation coefficient is a "statistical measure that calculates the strength of the relationship between the relative movements of two variables". It's denoted by r and its always between -1 and 1.
The sum of squares "is the sum of the square of variation, where variation is defined as the spread between each individual value and the grand mean"
When we conduct a multiple regression we want to know about the relationship between several independent or predictor variables and a dependent or criterion variable.
n=110,

Part a
The slope is given by this formula:
If we replace we got:
We can find the intercept with the following formula
We can find the average for x and y like this:
And replacing we got:
Part b
In order to calculate the correlation coefficient we can use this formula:
For our case we have this:
n=110,
So we can find the correlation coefficient replacing like this:
And the determination coeffecient is
To find the area, you will need to times the length with the width.
So,
2.25*1.8=4.05 meters
1m=100cm
4.05m=405cm
Hope this helps.
Answer:
a.


b.


c.
Attached file
d.
Apparently the practice of smoking reduces the ability to fall asleep, demanding much more time in individuals who smoke, than in those who do not smoke.
Step-by-step explanation:
a, b) For the group of smoking individuals, the average time it takes to fall asleep and the standard deviation of those times is:


a, b) For the group of non-smoking individuals, the average time it takes to fall asleep and the standard deviation of those times is:


c. In the attached file you can see the diagram of points for the times, in the smoking and non-smoking groups.
d. Apparently the practice of smoking reduces the ability to fall asleep, demanding much more time in individuals who smoke, than in those who do not smoke.
We have the expression:
3x(x-12x) + 3x^2 - 2(x-2)^2
First, we will expand the power 2 bracket as follows:
3x(x-12x) + 3x^2 - 2(x^2 - 4x +4)
Then, we will get rid of the brackets as follows:
3x^2 - 36x^2 + 3x^2 - 2x^2 + 8x - 8
Now, we will gather the like terms and add them as follows:
-32 x^2 + 8x - 8
We can take the 8 as a common factor:
8 ( -4x^2 + x -1)