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2 years ago

What is the slope of the line through the points (-2, -1) and (4, 3)?

Mathematics

1 answer:

Natalka [10]2 years ago

8 0

Answer:

#2 option: $\frac{2}{3}$

Step-by-step explanation:

$slope=\frac{rise}{run} =\frac{y^2-y^1}{x^2-x^1}$

$\frac{3-(-1)}{4-(-2)}=\frac{-4}{-6} =\frac{-2}{-3} =\frac{2}{3}$

= $\frac{2}{3}$

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Find the value of x. (16x-4)° 58° (9x-6)°

mars1129 [50]

16x - 4 + 58 + 9x - 6 = 180
25x + 48 = 180
25x = 132
x = 5.28

5 0

3 years ago

My daughter needs help and I don't understand the question ethier.

WINSTONCH [101]

So firstly, let's figure out the expression for a singular goody bag. Since there's 2 of each item, a single goody bag is going to be $(1.07*2+0.85*2+2.12*2)$

Now since we have 7 friends who are all getting 1 goody bag, multiply the cost of the goody bag by 7, and our expression is $7(1.07*2+0.85*2+2.12*2)$ . Now we can solve it from there.

Firstly, solve the multiplication inside the parentheses: $7(2.14+1.7+4.24)$

Now add up what's inside the parentheses: $7(8.08)$

Lastly, multiply and your answer will be $56.56

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3 years ago

At a recent county fair, you observed that at one stand people's weight was forecasted, and were surprised by the accuracy (with

MatroZZZ [7]

Answer:

a)Slope: $\hat \beta_1 =\frac{7625.9}{1248.9}=6.106$

Intercept: $\hat \beta_o = 157.955 -6.106 (69.686)=-267.548$

b) $r=\frac{7625.9}{\sqrt{[1248.9][94228.8]}}=0.657$

And the determination coeffecient is $r^2 = 0.657^2 =0.432$

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, $\sum x_i y_i = \sum (X-\bar X)(Y-\bar Y) =7625.9,\sum x^2_i=\sum (x-\bar x)^2 =1248.9 , sum y^2_i=\sum(y-\bar y)^2 =94228.8$

$\sum Y_i =17375 , \sum X_i = 7665.5$

Part a

The slope is given by this formula:

$\hat \beta_1 =\frac{\sum (x-\bar x) (y-\bar y)}{\sum (x-\bar x )^2}$

If we replace we got:

$\hat \beta_1 =\frac{7625.9}{1248.9}=6.106$

We can find the intercept with the following formula

$\hat \beta_o = \bar y -\hat \beta_1 \bar x$

We can find the average for x and y like this:

$\bar X=7665.5/110 =69.686, \bar y= 17375/110=157.955$

And replacing we got:

$\hat \beta_o = 157.955 -6.106 (69.686)=-267.548$

Part b

In order to calculate the correlation coefficient we can use this formula:

$r=\frac{\sum (x-\bar x)(y-\bar y) }{\sqrt{[\sum (x-\bar x)^2][\sum(y-\bar y)^2]}}$

For our case we have this:

n=110, $\sum x_i y_i = \sum (X-\bar X)(Y-\bar Y) =7625.9,\sum x^2_i=\sum (x-\bar x)^2 =1248.9 , sum y^2_i=\sum(y-\bar y)^2 =94228.8$

So we can find the correlation coefficient replacing like this:

$r=\frac{7625.9}{\sqrt{[1248.9][94228.8]}}=0.657$

And the determination coeffecient is $r^2 = 0.657^2 =0.432$

6 0

4 years ago

I know the answer but the calculator doesn't seem to give the right one

Diano4ka-milaya [45]

Answer:

Make sure the mode is on degree and not radian! Common mistake

6 0

3 years ago

Think of a situation when someone would need to make a measurement with extreme precision. Describe the setting, why the measure

makkiz [27]

Answer:

Ok, suppose you want to create a battery that fits exactly in the hole that is already created for an electric device, like a cellphone for example.

If the battery is slightly bigger, it will not enter the socket, and the battery will be a loss in time and resources.

If the battery is slightly smaller, it will move when it is in the socket, so the cell phone will shut down randomly when you move it, then this battery is also a loss in time and resources.

So you need to measure exactly the socket in order to make a battery that fits exactly inside of it with very good precision.

This example can be extended for any electronic piece that you need to fit in a given space (for example in microtechnology, the precision of the measures is must be extreme because working with those things is really expensive and you can not mess up with the dimensions of the pieces)

5 0

3 years ago

What is the slope of the line through the points (-2, -1) and (4, 3)? ​

What is the slope of the line through the points (-2, -1) and (4, 3)?