Can anyone please help me with question need help please

Factorize x^2+3x-ax-3a

Kobotan [32]

Answer:

=−ax+x2−3a+3x

Step-by-step explanation:

3 0

3 years ago

Alex is creating an outdoor structure out of two 12 foot boards. The boards must have an angle of elevation

Whitepunk [10]

Answer:

5.0 ft - 5.6 ft

Step-by-step explanation:

Given that the structure is to be made using two 12 foot boards, then we expect the total perimeter to be equal to (2*12)= 24 ft.

Using the angle of elevation, 40° and the width of 8 ft then you can apply the formula for tangent of a triangle where ;

Tan α = opposite side length/adjacent length

Tan 40°= h/8

h= 8 tan 40° = 6.71 ft

Applying the cosine of an angle formula to find the length of the sliding side

Cosine β = adjacent length /hypotenuse

Cosine 40°= 8/ sliding side length

sliding side length = 8/cosine 40° =10.44 ft

Checking the perimeter = 10.44 +8+6.71= 25.15 ft

This is more than the total lengths of the boards, so you need to adjust the height as;

24 - 18.44 = 5.56 ft ,thus the height should be less or equal to 5.56 ft

h≤ 5.6 ft

6 0

3 years ago

The 2008 Workplace Productivity Survey, commissioned by LexisNexis and prepared by WorldOne Research, included the question, "Ho

vitfil [10]

Answer:

Therefore, the sampling distribution of $\bar{x}$ is normal with a mean equal to 9 hours and a standard deviation of 0.7969 hours.

The 95% interval estimate of the population mean $\mu$ is

LCL = 7.431 hours to UCL = 10.569 hours

Step-by-step explanation:

Let X be the number of hours a legal professional works on a typical workday. Imagine that X is normally distributed with a known standard deviation of 12.6.

The population standard deviation is

$\sigma = 12.6 \: hours$

A sample of 250 legal professionals was surveyed, and the sample's mean response was 9 hours.

The sample size is

$n = 250$

The sample mean is

$\bar{x} = 9 \: hours$

Since the sample size is quite large then according to the central limit theorem, the sample mean is approximately normally distributed.

The population mean would be the same as the sample mean that is

$\mu = \bar{x} = 9 \: hours$

The sample standard deviation would be

$s = {\frac{\sigma}{\sqrt{n} }$

Where is the population standard deviation and n is the sample size.

$s = {\frac{12.6}{\sqrt{250} }$

$s = 0.7969 \: hours$

Therefore, the sampling distribution of $\bar{x}$ is normal with a mean equal to 9 hours and a standard deviation of 0.7969 hours.

The population mean confidence interval is given by

$\text {confidence interval} = \mu \pm MoE\\\\$

Where the margin of error is given by

$$ MoE = t_{\alpha/2}(\frac{s}{\sqrt{n} } ) $ \\\\$

Where n is the sampling size, s is the sample standard deviation and is the t-score corresponding to a 95% confidence level.

The t-score corresponding to a 95% confidence level is

Significance level = α = 1 - 0.95 = 0.05/2 = 0.025

Degree of freedom = n - 1 = 250 - 1 = 249

From the t-table at α = 0.025 and DoF = 249

t-score = 1.9695

$MoE = t_{\alpha/2}(\frac{\sigma}{\sqrt{n} } ) \\\\MoE = 1.9695\cdot \frac{12.6}{\sqrt{250} } \\\\MoE = 1.9695\cdot 0.7969\\\\MoE = 1.569\\\\$

So the required 95% confidence interval is

$\text {confidence interval} = \mu \pm MoE\\\\\text {confidence interval} = 9 \pm 1.569\\\\\text {LCI } = 9 - 1.569 = 7.431\\\\\text {UCI } = 9 + 1.569 = 10.569$

The 95% interval estimate of the population mean $\mu$ is

LCL = 7.431 hours to UCL = 10.569 hours

8 0

3 years ago

At a amusement ,park 360 visitors rode the roller coaster in 3 hours.Write and solve a proportion to find the number of visitors

Pachacha [2.7K]

First you need to find out about how many people went on the roller coaster in one hour by doing 360 divided by 3 and you would get 120. So then you would try to find out how many people went on the coaster in 7 hours by doing 360 times 2 because 3 hours multiplied by 2 is 6 and you would do that to find out how many people went on the coaster in 6 hours, and you would get 720. Next, you have 1 more round of people, so you need to do 720 + 120 which is 840. So about 840 people rode the coaster in 7 hours. Hope this helped.

6 0

3 years ago

Complete the statements about circle j

-BARSIC- [3]

Answer:minor arc 152 & major arc 298

Step-by-step explanation:

7 0

3 years ago

Can anyone please help me with question need help please ​

Can anyone please help me with question need help please