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3 years ago

6x - 5y = 11 y = 7x + 21 What is the correct answer to this problem?

Mathematics

1 answer:

evablogger [386]3 years ago

3 0

Answer:

X=-4, y=-7

Step-by-step explanation:

6x-5y=11. 1st equation

y=7x+21 2nd equation

6x-5(7x+21)=11. Sub value of y in 2nd equation (7x+22) into 1st equation

6x-35x-105=11. Solve by distributative property

-29x-105=11. Add x values

-29x=116. add 105 to both sides

x=-4. Solve for x

solve for y:

y=7x+21

y=7(-4)+21

y=-28+21

y=-7

check answer by substituting x and y into either equation

6x-5y=11

6(-4)-5(-7)=11

-24+35=11

11=11

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Answer:

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Option A) The measures of variation are not very useful because when searching for a room, low prices, location, and good accommodations are more important than the amount of variation in the area.

Step-by-step explanation:

We are given the data for prices in dollars for one night at different hotels in a certain region.

234, 160, 119, 131, 218, 207, 146, 141

Range:

Sorted data: 119, 131, 141, 146, 160, 207, 218, 234

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Standard Deviation:

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where $x_i$ are data points, $\bar{x}$ is the mean and n is the number of observations.

$Mean = \displaystyle\frac{\text{Sum of all observations}}{\text{Total number of observation}}$

$Mean =\displaystyle\frac{1356}{8} = 169.5$

Sum of squares of differences = 4160.25 + 90.25 + 2550.25 + 1482.25 + 2352.25 + 1406.25 + 552.25 + 812.25 = 13406

$\sigma = \sqrt{\dfrac{13406}{7}} = 43.76\$$

Variance =

$\sigma^2 = 1915.142\$$

Measure of variance for someone searching for room:

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3 years ago

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Given: In triangle MNO shown below, segment NP is an altitude from the right angle.

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