All categories

3 years ago

Given the function: f(x) = 2x2 - 3x + 8, find f(-2).

Mathematics

1 answer:

Vaselesa [24]3 years ago

5 0

Answer: 22

<u>Step-by-step explanation:</u>

f(x) = 2x² - 3x + 8

f(-2) = 2(-2)² - 3(-2) + 8

= 2(4) + 6 + 8

= 8 + 6 + 8

= 22

You might be interested in

We would like to create a confidence interval.

Vlada [557]

Answer:

c.A 90% confidence level and a sample size of 300 subjects.

Step-by-step explanation:

In a sample with a number n of people surveyed with a probability of a success of $\pi$ , and a confidence level $1-\alpha$ , we have the confidence interval with a margin of error of:

$M = z\sqrt{\frac{\pi(1-\pi)}{n}}$

In which

z is the zscore that has a pvalue of $1 - \frac{\alpha}{2}$ .

In this problem

The proportions are the same for all the options, so we are going to write our margins of error as functions of $\sqrt{\pi(1-\pi)}$

a.A 99% confidence level and a sample size of 50 subjects.

$n = 50$

99% confidence interval

So $\alpha = 0.01$ , z is the value of Z that has a pvalue of $1 - \frac{0.01}{2} = 0.995$ , so $Z = 2.575$ .

The margin of error is

$M = z\sqrt{\frac{\pi(1-\pi)}{n}} = \frac{2.575}{\sqrt{50}}\sqrt{\pi(1-\pi)} = 0.3642\sqrt{\pi(1-\pi)}$

b.A 90% confidence level and a sample size of 50 subjects.

$n = 50$

90% confidence interval

So $\alpha = 0.1$ , z is the value of Z that has a pvalue of $1 - \frac{0.1}{2} = 0.95$ , so $Z = 1.645$ .

The margin of error is

$M = z\sqrt{\frac{\pi(1-\pi)}{n}} = \frac{1.645}{\sqrt{50}}\sqrt{\pi(1-\pi)} = 0.2623\sqrt{\pi(1-\pi)}$

c.A 90% confidence level and a sample size of 300 subjects.

$n = 300$

90% confidence interval

So $\alpha = 0.1$ , z is the value of Z that has a pvalue of $1 - \frac{0.1}{2} = 0.95$ , so $Z = 1.645$ .

The margin of error is

$M = z\sqrt{\frac{\pi(1-\pi)}{n}} = \frac{1.645}{\sqrt{300}}\sqrt{\pi(1-\pi)} = 0.0950\sqrt{\pi(1-\pi)}$

This produces smallest margin of error.

d.A 99% confidence level and a sample size of 300 subjects.

$n = 300$

99% confidence interval

So $\alpha = 0.01$ , z is the value of Z that has a pvalue of $1 - \frac{0.01}{2} = 0.995$ , so $Z = 2.575$ .

The margin of error is

$M = z\sqrt{\frac{\pi(1-\pi)}{n}} = \frac{2.575}{\sqrt{300}}\sqrt{\pi(1-\pi)} = 0.1487\sqrt{\pi(1-\pi)}$

6 0

3 years ago

If point p partitions line BA,what would be the part to whole ratio

IRINA_888 [86]

Answer:

4 / 5

Step-by-step explanation:

From the image attached, Line BA is divided into a total of 5 equal proportions (or intervals). Point P is placed at the 4th proportion of the divided line, also the distance between point P and point A is 1 propotion. The ratio in which point P divides the line BA is given as:

Ratio = BP : PA = 4 : 1

Ratio = 4 : 1

The part to whole ratio If point p partitions line BA = BP / BA = 4 / 5

Part to whole ratio = 4/5

3 0

3 years ago

Graph the function and answer each of the following questions, f(x) = -3x + 5

olga2289 [7]

A. 5
B. -3/1
C. Negative
D. You have to go down 3 over to the right one from where your y-intercept is.

To plot the y intercept plot (0,5)
To plot the next point go down 3 over 1 to the right from the y-ing

3 0

3 years ago

Which of the following equations correctly represents the law of cosines?

dusya [7]

Answer:

Step-by-step explanation:

7 0

3 years ago

Please help.<br> Its a True or False question.

faust18 [17]

Answer:

1. False