4. Seven times the difference of a number k and five is twenty-onel

Anit [1.1K]

Well first you have to add common like terms in this case 2r and -6r to get -4r now your equation is -4r+8=40, now subtract 8 from both sides to leave r by itself and get -4r=32, now divide both sides by -4 to get r=-8

Hope this helps

3 0

3 years ago

Read 2 more answers

verify that the fucntion satisfies the three hypotheses of rolles theorem on the given interval . then find all numbers c that s

Ghella [55]

The roots of the polynomial x^3 − 2x^2 − 4x + 2 are:

x1 = 0.42801

x2 = −1.51414

x3 = 3.08613

x1 and x2 are in the desired interval [-2, 2]

f'(x) = 3x^2 - 4x - 4

so we have:

3x^2 - 4x - 4 = 0

x = ( 4 +- √(16 + 48) )/6

x_1 = -4/6 = -0.66

x_ 2 = 2

According to Rolle's theorem, we have one point in between:

x1 = 0.42801 and x2 = −1.51414

where f'(x) = 0, and that is x_1 = -0.66

so we see that Rolle's theorem holds in our function.

4 0

3 years ago

Hi if u could help me that would be great, have a nice day!!!

LenaWriter [7]

Hey there! I'm happy to help!

-------------------------------------------------------------------

OVERVIEW

Random sampling is when you take a sample of something completely at random. This is done to avoid bias and other stuff like that. It makes the data a lot more pure, real, and factual.

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CHOOSING THE ANSWER

OPTION A: A SCHOOL NEWSPAPER ASKS TEACHERS IN THAT MIDDLE SCHOOL HOW THEY FEEL ABOUT THE BEHAVIOR OF TWELVE YEAR OLD BOYS.

Does this seem very random to you? They're asking all the teachers who work at a certain junior high to talk about twelve year old boys. But, the teachers are definitely going to have some sort of bias towards twelve year old boys because they work with them, and since all of the samples are teachers, this is going to have biased data. Therefore, answer A is incorrect.

OPTION B: A NATIONAL SURVEY COMPANY PICKS ONE PHONE NUMBER FROM EACH AREA CODE IN AMERICA TO CALL AND ASK FOR AN OPINION ON CURRENT POLITICAL ISSUES.

This definitely seems a lot more random. There is only one phone number from each area code and there are many area codes in the United States so you get a bit of what everyone thinks about an issue. There is no bias because there is one random phone number and there are many different places this is done. Therefore, option B is correct.

OPTION C: MIGRANT WORKERS ARE SURVEYED ON THEIR OPINION OF MANDATORY HEALTH INSURANCE FOR COMPANIES.

This is not very random because they are asking a specific group of workers about a company and business ordeal. It is not very random because the migrant workers are specifically being asked, not random people. Therefore, option C is incorrect.

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THE SOLUTION

Therefore, Option B is the correct answer.

I hope that this helps! Have a wonderful day!

7 0

3 years ago

Solve the inequality 5x+2 < 32

AnnyKZ [126]

Answer:

x<6

Step-by-step explanation:

First, let's work on the left hand side of your inequality, the 5x+2

This means, for instance, to see if it can be simplified at all.

Multiply x and 5

Multiply x and 1

The x just gets copied along.

The answer is x

x

5*x evaluates to 5x

5*x+2 evaluates to 5x+2

So, all-in-all, the left hand side of your inequality can be written as: 5x+2

Now, let's work on the right hand side of your inequality, the 32

The right hand side of your inequality can be written as: 32

So with these (any) simplifications, the inequality we'll set out to solve is:

5x+2 ‹ 32

Move the 2 to the right hand side by subtracting 2 from both sides, like this:

From the left hand side:

2 - 2 = 0

The answer is 5x

From the right hand side:

32 - 2 = 30

The answer is 30

Now, the inequality reads:

5x ‹ 30

To isolate the x, we have to divide both sides of the inequality by the other "stuff" (variables or coefficients)

around the x on the left side of the inequality.

The last step is to divide both sides of the inequality by 5 like this:

To divide x by 1

The x just gets copied along in the numerator.

The answer is x

5x ÷ 5 = x

30 ÷ 5 = 6

The solution to your inequality is:

x ‹ 6

8 0

3 years ago

Read 2 more answers

Using 50 boxes of nails a carpenter a

lapo4ka [179]

450=50x this should be correct :)

8 0

3 years ago