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3 years ago

9

PLEASE HELP .Which of the following choices will evaluate the function ƒ(x) = -(-x), when x = -3? 3 -1 -3 None of these choices

are correct.

1 answer:

LenaWriter [7]3 years ago

8 0

Answer:

3

Step-by-step explanation:

You might be interested in

The least-squares regression model y =−3.4+5.2x and correlation coefficient r=−0.66 were calculated for a set of bivariate data

Makovka662 [10]

Answer:

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

For this case the value of r = -0.66

Now we can calculate the determination coeffcient:

$r^2 = (-0.66)^2 = 0.4356$

And then we can conclude that 43.56% of the variation in y can be explained by the explanatory variable

And then 100-43.56 = 56.44 % of the variation in y that cannot be explained by the explanatory variable

Step-by-step explanation:

For this case we need to calculate the slope with the following formula:

$m=\frac{S_{xy}}{S_{xx}}$

Where:

$S_{xy}=\sum_{i=1}^n x_i y_i -\frac{(\sum_{i=1}^n x_i)(\sum_{i=1}^n y_i)}{n}$

$S_{xx}=\sum_{i=1}^n x^2_i -\frac{(\sum_{i=1}^n x_i)^2}{n}$

$\bar x= \frac{\sum x_i}{n}$

$\bar y= \frac{\sum y_i}{n}$

And we can find the intercept using this:

$b=\bar y -m \bar x$

And the model obtained for this case is:

$y = -3.4 +5.2 x$

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.

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

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

For this case the value of r = -0.66

Now we can calculate the determination coeffcient:

$r^2 = (-0.66)^2 = 0.4356$

And then we can conclude that 43.56% of the variation in y can be explained by the explanatory variable

And then 100-43.56 = 56.44 % of the variation in y that cannot be explained by the explanatory variable

8 0

3 years ago

Select the equation of a line that is parallel to the line 4y=3x+5 use the attached image below to help you out!!!

BARSIC [14]

Answer:

B

Step-by-step explanation:

Parallel lines have the same slope. The slope of the given line is 3/4. Line B has the same slope.

7 0

3 years ago

Read 2 more answers

Camilla baked 15 cookies with 3 scoops of flour. How many scoops of flour does Camilla need in order to bake 20 cookies? Solve u

omeli [17]

Answer:

camilla needs 4 scoops of flow because 3 is related to 15 bc "5x3=15" and that gives us to only need 1 more cup to get 20 cookies

7 0

2 years ago

What is the simplified form of the quantity of x plus 4, all over the quantity of 7 − the quantity of x plus 3, all over the qua

scoundrel [369]

$\frac{x + 4}{7} -\frac{x + 3}{x + 5} =\frac{(x + 4)(x + 5)}{7(x + 5)} -\frac{7(x + 3)}{7(x + 5)} =\frac{x(x + 5) + 4(x + 5)}{7(x) + 7(5)} - \frac{7(x) + 7(3)}{7(x) + 7(5)} =\frac{x(x) + x(5) + 4(x) + 4(5)}{7x + 35} - \frac{7x + 21}{7x + 35} =\frac{x^{2} + 5x + 4x + 20}{7x + 35} -\frac{7x + 21}{7x + 35} =\frac{x^{2} + 9x + 20}{7x + 35} - \frac{7x + 21}{7x + 35} =\frac{(x^{2} + 9x + 20) - (7x + 21)}{7x + 35} =\frac{x^{2} + (9x - 7x) + (20 - 21)}{7x + 35} =\frac{x^{2} + 2x -1}{7x + 35}$

3 0

3 years ago

6. Find the area of a triangle with sides a = 5, b = 8, and c = 11.

Colt1911 [192]

<h2>20</h2>

Hi, I’m Lena and I’ll be here to answer your question with a good-quality answer. If there's something I can improve, let me know! ツ

♡ Let’s look at the main important things that will lead you in the correct path.

♥ <em>a </em>+<em> b</em> usually = <em>c!</em> Unless the book asks you to find a specific variable, you will most likely be looking for <em>c</em>.

♥ <em>A</em> = <em>bh</em>/2! This is the formula for the area of a triangle. You can also read this as A = base * height/2. The good thing about this formula is you don't need a picture. You can write it as <em>a</em> * b<em> </em>or <em>b</em> * <em>a!</em>

<em />

♡ Now, let's solve!

♥ Plug the numbers into the formula: 5*8/2.

♥ Solve! In this case, we do not need c: 40/2 = 20.

Your answer should be 20! Please do not hesitate to ask me any questions.

3 0

3 years ago