NEED HELP Solve using elimination. –8x − 4y =

How can the average rate of change be identified for a function?

Digiron [165]

Answer:

$Rateofchange=\frac{f(x_2)-f(x_1)}{x_2-x_1}$

where x₁ and x₂ are values in the interval [x,y] respectively

Step-by-step explanation:

Well, first to determine the average rate of change of a function, you should have the interval of the values of x for the function.

So lets assume you have a function;

$f(x)=x^3-4x$

And the interval as [1,3]

Then the average rate of change for the function f(x) will be;

$=\frac{f(x_2)-f(x_1)}{x_2-x_1}$

where x₁ and x₂ are the interval coordinates x,y respectively. In this case x₁=1 and x₂=3

To find the average rate of change in this example will be;

$=\frac{f(x_2)-f(x_1)}{x_2-x_1} \\\\=f(x_2)=f(3)=3^3-4(3)=27-12=15\\\\=f(x_1)=f(1)=1^3-4(1)=1-4=-3\\\\\\=x_2-x_1=3-1=2\\\\\\=\frac{15--3}{2} \\\\=\frac{18}{2} =9$

8 0

4 years ago

A random survey of 1000 students nationwide showed a mean ACT score of 21.1. Ohio was not used. A survey of 500 randomly selecte

vodka [1.7K]

Answer:

We conclude that the mean Ohio score is below the national average.

Step-by-step explanation:

We are given that a random survey of 1000 students nationwide showed a mean ACT score of 21.1. Ohio was not used.

A survey of 500 randomly selected Ohio scores showed a mean of 20.8. The population standard deviation is 3.

Let $\mu$ = mean Ohio scores.

So, Null Hypothesis, $H_0$ : $\mu$ $\geq$ 21.1 {means that the mean Ohio score is above or equal the national average}

Alternate Hypothesis, $H_A$ : $\mu$ < 21.1 {means that the mean Ohio score is below the national average}

The test statistics that would be used here One-sample z test statistics as we know about population standard deviation;

T.S. = $\frac{\bar X-\mu}{\frac{\sigma}{\sqrt{n}}}$ ~ N(0,1)

where, $\bar X$ = sample mean Ohio score = 20.8

$\sigma$ = population standard deviation = 3

n = sample of Ohio = 500

So, test statistics = $\frac{20.8-21.1}{\frac{3}{\sqrt{500}}}$

= -2.24

The value of z test statistics is -2.24.

Now, at 0.1 significance level the z table gives critical value of -1.2816 for left-tailed test. Since our test statistics is less than the critical values of z as -2.24 < 1.2816, so we have sufficient evidence to reject our null hypothesis as it will fall in the rejection region due to which we reject our null hypothesis.

Therefore, we conclude that the mean Ohio score is below the national average.

4 0

3 years ago

Please help me this is important to my grade

defon

Answer:

C. x = 6

Step-by-step explanation:

2*6 + 4 = 16

6 0

3 years ago

I am an improper fraction whose numerator and denominator are made of odd digits only. In my simplest form, my representation as

ASHA 777 [7]

Answer:

The fraction is = $\frac{21}{9}$

Step-by-step explanation:

In simplest form the fraction is represented in mixed number as $2\frac{1}{3}$ .

The fraction form of the mixed number can be given as :

$2\frac{1}{3}=\frac{7}{3}$

Let the fraction be = $\frac{7x}{3x}$ [As multiplying same numbers to numerator and denominator does not affect the proportion.

Sum of numerator and denominator is = 30

This, can be represented as:

$7x+3x=30$

Solving for $x$ .

$10x=30$

Dividing both sides by 10.

$\frac{10x}{10}=\frac{30}{10}$

$x=3$

So, the fraction will be = $\frac{7\times 3}{3\times 3}$

⇒ $\frac{21}{9}$

3 0

3 years ago

There are 4 people at a party. Consider the random variable X=’number of people having the same birthday ’ (match only month, N=

yulyashka [42]

Answer:

S = {0,2,3,4}

P(X=0) = 0.573 , P(X=2) = 0.401 , P(x=3) = 0.025, P(X=4) = 0.001

Mean = 0.879

Standard Deviation = 1.033

Step-by-step explanation:

Let the number of people having same birth month be = x

The number of ways of distributing the birthdays of the 4 men = (12*12*12*12)

The number of ways of distributing their birthdays = 12⁴

The sample space, S = { 0,2,3,4} (since 1 person cannot share birthday with himself)

P(X = 0) = $\frac{12P4}{12^{4} }$

P(X=0) = 0.573

P(X=2) = P(2 months are common) P(1 month is common, 1 month is not common)

P(X=2) = $\frac{3C2 * 12P2}{12^{4} } + \frac{4C2 * 12P3}{12^{4} }$

P(X=2) = 0.401

P(X=3) = $\frac{4C3 * 12P2}{12^{4} }$

P(x=3) = 0.025

P(X=4) = $\frac{12}{12^{4} }$

P(X=4) = 0.001

Mean, $\mu = \sum xP(x)$

$\mu = (0*0.573) + (2*0.401) + (3*0.025) + (4*0.001)\\\mu = 0.879$

Standard deviation, $SD = \sqrt{\sum x^{2} P(x) - \mu^{2}} \\SD =\sqrt{ [ (0^{2} * 0.573) + (2^{2} * 0.401) + (3^{2} * 0.025) + (4^{2} * 0.001)] - 0.879^{2}}$

SD = 1.033

4 0

3 years ago

NEED HELP Solve using elimination. –8x − 4y = –20 8x + 5y = 13