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2 years ago

A rectangular retaining wall has an area of

Mathematics

1 answer:

Veronika [31]2 years ago

8 0

Answer:

The height of wall is 3 feet and length of wall is 5 feet

Step-by-step explanation:

Given as :

The Area of retaining wall = 15 square feet

Let The width of wall = W feet

The Height of wall = ( W - 2 ) feet

Now, Area of Rectangle = Height width

Or , 15 ft² = ( W - 2 ) ft × W ft

Or, 15 = W² - 2 W

Or, W² - 2 W - 15 = 0

Or, W² - 5 W + 3 W - 15 = 0

Or, W ( W - 5 ) + 3 ( W - 5 ) = 0

So , ( W - 5 ) ( W + 3 ) = 0

So, W = 5 , - 3

∴ The width of wall = W = 5 feet

And The Height of wall = ( W - 2 ) = 5 - 2 = 3 feet

Hence The height of wall is 3 feet and length of wall is 5 feet. Answer

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what abiotic factor is changing the ecosystem of Lake Washington,and how has this factor changed over time.

raketka [301]

Answer:

Step-by-step explanation:

Temperature is the abiotic factor that is changing the ecosystem. Both the top layer temperature and the overall temperature of the lake are increasing. The warmer temperatures have delayed the yearly springtime mixing of warm and cold water in the lake.

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2 years ago

Assume a simple random sample of 10 BMIs with a standard deviation of 1.186 is selected from a normally distributed population o

kirza4 [7]

Answer:

a) H0: $\sigma = 1.34$

H1: $\sigma \neq 1.34$

b) $df = n-1= 10-1=9$

And the critical values with $\alpha/2=0.005$ on each tail are:

$\chi_{\alpha/2}= 1.735, \chi_{1-\alpha/2}= 23.589$

c) $t=(10-1) [\frac{1.186}{1.34}]^2 =7.05$

d) For this case since the critical value is not higher or lower than the critical values we have enough evidence to FAIL to reject the null hypothesis and we can conclude that the true deviation is not significantly different from 1.34

Step-by-step explanation:

Information provided

n = 10 sample size

s= 1.186 the sample deviation

$\sigma_o =1.34$ the value that we want to test

$p_v$ represent the p value for the test

t represent the statistic (chi square test)

$\alpha=0.01$ significance level

Part a

On this case we want to test if the true deviation is 1,34 or no, so the system of hypothesis are:

H0: $\sigma = 1.34$

H1: $\sigma \neq 1.34$

The statistic is given by:

$t=(n-1) [\frac{s}{\sigma_o}]^2$

Part b

The degrees of freedom are given by:

$df = n-1= 10-1=9$

And the critical values with $\alpha/2=0.005$ on each tail are:

$\chi_{\alpha/2}= 1.735, \chi_{1-\alpha/2}= 23.589$

Part c

Replacing the info we got:

$t=(10-1) [\frac{1.186}{1.34}]^2 =7.05$

Part d

For this case since the critical value is not higher or lower than the critical values we have enough evidence to FAIL to reject the null hypothesis and we can conclude that the true deviation is not significantly different from 1.34

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2 years ago

Identify the parent function that can be used to graph the function f(x)=-9(x+5)^2

svetoff [14.1K]

Answer:

Option a) f(x)=x^2

Step-by-step explanation:

The parent function that can be used to graph the function f(x)=-9(x+5)^2 is f(x)=x^2

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2 years ago

Amirah's family is driving to her uncle's house. The family travels 383.5 miles between 10:15 am and 4:45 pm. Calculate the fami

ddd [48]

Answer:

The family's average rate of travel for the day was 59.0 MPH.

Step-by-step explanation:

From 10:15AM to 4:45PM, they travelled a distance of 383.5 miles and a total of 6 hours and 30 minutes.

There are 60 minutes in an hour. 30 minutes translates into 1/2 an hour or .5

So, 6.5 hours and a total distance of 383.5 miles.

Velocity (MPH) = Distance (in miles) / Time (in hours)

MPH means Miles Per Hour

Variables:

Velocity (MPH) = x

Distance (in miles) = 383.5

Time (in hours) = 6.5

Plug in the variables into the formula

x = 383.5 / 6.5

Divide

x = 59.0 MPH

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2 years ago

Read 2 more answers

Jesse worked forty hours this past week assuming he makes $12 an hour how much was withheld from his paycheck by his employer fo

Alecsey [184]

He made 12*40=480 dollars in total. 0.0765*480=36.72 dollars were withheld.

6 0

3 years ago

Read 2 more answers