All categories

2 years ago

Solve 2x + 12 = -4. show wrk

Mathematics

2 answers:

mel-nik [20]2 years ago

5 0

2x +12=-4

2x= -4-12

2x=-16

x=-16/2

x= -8

labwork [276]2 years ago

4 0

Step-by-step explanation:

2x+12=-4

2x=-4-12

x=-16/2

x=-8

hope this helps you

have a good day.

You might be interested in

The gradient of the line y= -2x -3

N76 [4]

Answer:

-2

Step-by-step explanation:

The equation of the line is written in y=mx+c form, where m is the gradient and c is the y-intercept.

In this case, your m is a -2 and your c is a -3.

Hence the gradient of the line is -2.

5 0

3 years ago

What is the area of this parallelogram? the perimeter is 19

Assoli18 [71]

Answer:

its 22 <3

Step-by-step explanation:

a=bh

(area = base x height)

base = 5.5

height = 4

5.5 x 4 = 22 :)

6 0

3 years ago

Help pls I need it ily

Natalka [10]

The answer is answer B!

6 0

2 years ago

A store had a number of chairs in stock at the beginning of the week. During the week, 66 chairs were sold, leaving the store wi

Ann [662]

They had 81 chairs at the beginning

6 0

3 years ago

Read 2 more answers

An experiment to investigate the survival time in hours of an electronic component consists of placing the parts in a test cell

mixer [17]

Answer:

a) The sample mean is of 49 and the sample standard deviation is of 11.7.

b) The range of the true mean at 90% confidence level is of 9.62 hours.

c) The prediction interval, at a 90% confidence level, of it's failure time is between 39.38 hours and 58.62 hours.

Step-by-step explanation:

Question a:

Sample mean:

$\overline{x} = \frac{34+40+46+49+61+64}{6} = 49$

Sample standard deviation:

$s = sqrt{\frac{(34-49)^2+(40-49)^2+(46-49)^2+(49-49)^2+(61-49)^2+(64-49)^2}{5}} = 11.7$

The sample mean is of 49 and the sample standard deviation is of 11.7.

b)Determine the range of the true mean at 90% confidence level.

We have to find the margin of error of the confidence interval. Since we have the standard deviation for the sample, the t-distribution is used.

The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So

df = 6 - 1 = 5

90% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 5 degrees of freedom(y-axis) and a confidence level of $1 - \frac{1 - 0.9}{2} = 0.95$ . So we have T = 2.0.150

The margin of error is:

$M = T\frac{s}{\sqrt{n}}$

In which s is the standard deviation of the sample and n is the size of the sample. So

$M = 2.0150\frac{11.7}{\sqrt{6}} = 9.62$

The range of the true mean at 90% confidence level is of 9.62 hours.

(c)If a seventh sample is tested, what is the prediction interval (90% confidence level) of its failure time.

This is the confidence interval, so:

The lower end of the interval is the sample mean subtracted by M. So it is 49 - 9.62 = 39.38 hours.

The upper end of the interval is the sample mean added to M. So it is 49 + 9.62 = 58.62 hours.

The prediction interval, at a 90% confidence level, of it's failure time is between 39.38 hours and 58.62 hours.

4 0

3 years ago