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3 years ago

The graph below represents the solution set of which inequality

Mathematics

2 answers:

spayn [35]3 years ago

4 0

Answer:

Step-by-step explanation:

A. x^2 - 2x - 8 < 0

(x - 4)(x + 2) < 0

B. x^2 + 2x - 8 < 0

(x + 4)(x - 2) < 0

C. x^2 - 2x - 8 > 0

(x - 4)(x - 2) > 0

D. x^2 + 2x - 8 > 0

(x + 4)(x - 2) > 0

Since roots here are -4 and 2, the answer is either B or D.

When you test a point in the interval between -4 and 2, for example 0, it is negative.

So the answer is B.

Svetradugi [14.3K]3 years ago

3 0

Answer:

The answer is $x^2+2x-8$

Step-by-step explanation:

In order to determine the answer, we have two alternatives:

Solving every option and check which is correct.
Replacing two or three numbers in every option and check which is correct.

In this case, we use the second option because it is easier to replace a value and solving basic math operations. Also, if we choose a good first value, we will eliminate immediately some options.

We can choose values between -4 and 2. Every time we could choose 0 value, we should do it.

First value: $x=0$ . Replacing:

$-80$

We can see that the two first options are correct, the two last options are wrong.

Second value: $x=-3$ . Replacing:

$(-3)^2-2*(-3)-8$

We can see that the first option is wrong.

Finally, the correct option is the second one:

$x^2+2x-8$

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Aleksandr-060686 [28]

No. you are cheeting! you should do by your self, i can nelp you some of problem

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3 years ago

Write a real world problem for: 80-3x=53

Oxana [17]

Answer:

Sam had 80 dollars in his pocket. He was feeling generous, so he handed out equal amount of money to each of his friends. After he handed out the money, he had 53 dollars left. How much did Sam give out to each one of his friends?

Step-by-step explanation:

In this real-world problem, the money he had at the beginning resembles the 80 in the equation. The -3x is the money he gives out to each of his friends. The 53 on the right-hand side is the money he has left after he gives the money away.

6 0

3 years ago

A researcher wants to check the claim that convicted burglars spend less than 18.7 months in jail, on average. She takes a rando

vivado [14]

Answer:

a. No, there is not enough evidence to support the claim using a level of significance of 1%.

b. Null Hypothesis, $H_0$ : $\mu \geq$ 18.7 months

c. Alternate Hypothesis, $H_A$ : $\mu$ < 18.7 months

d. P-value of hypothesis test = 0.0199 or 1.99%

e. We conclude that the convicted burglars spend more than or equal to 18.7 months in jail, on average.

Step-by-step explanation:

We are given that a researcher wants to check the claim that convicted burglars spend less than 18.7 months in jail, on average.

She takes a random sample of 67 such cases from court files and finds that the mean is 16.8 months with a standard deviation of 7.3 months.

Let $\mu$ = true mean time convicted burglars spend in jail.

SO, Null Hypothesis, $H_0$ : $\mu \geq$ 18.7 months {means that the convicted burglars spend more than or equal to 18.7 months in jail, on average}

Alternate Hypothesis, $H_A$ : $\mu$ < 18.7 months {means that the convicted burglars spend less than 18.7 months in jail, on average}

The test statistics that will be used here is One-sample t test statistics as we don't know about the population standard deviation;

T.S. = $\frac{\bar X -\mu}{\frac{s}{\sqrt{n} } }$ ~ $t_n_-_1$

where, $\bar X$ = sample mean time spent in jail = 16.8 months

s = sample standard deviation = 7.3 months

n = sample of cases = 67

So, test statistics = $\frac{16.8-18.7}{\frac{7.3}{\sqrt{67} } }$ ~ $t_6_6$

= -2.13

Hence, the value of test statistics is -2.13.

Now, P-value of the test statistics is given by;

P-value = P( $t_6_6$ < -2.13) = 0.0199 or 1.99%

If the P-value of test statistics is more than the level of significance, then we will not reject our null hypothesis as it will not fall in the rejection region.

If the P-value of test statistics is less than the level of significance, then we will reject our null hypothesis as it will fall in the rejection region.

Now, here the P-value is 0.0199 or 1.99% which is clearly higher than the level of significance of 1%, so we will not reject our null hypothesis as it will not fall in the rejection region.

Therefore, we conclude that the convicted burglars spend more than or equal to 18.7 months in jail, on average.

6 0

3 years ago

I need help with this i don't know how to do it

damaskus [11]

Use the formula A= height*base/2

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3 years ago

If the height and radius of a cylinder are doubled, how will the volume of the cylinder be affected?

Leto [7]

If the height and radius of a cylinder are doubled, the volume of the cylinder will also double or will be higher. This is true because the formula for calculating cylinder’s volume is: V=πr2h; where r is the radius while h is the height. However, as you can see on the formula the radius has more effect than height.

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3 years ago