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salantis [7]
3 years ago
5

7x - 3y = 31 7x + y = -1 Please solve x and y

Mathematics
1 answer:
Vika [28.1K]3 years ago
4 0

Answer:

(1, -8)

y= -8

x= 1

Step-by-step explanation:

7x-3y= 31

7x+y= -1

solve the equation

7x-3y=31

7x= -1-y

substitute the value of 7x into an equation

-1-y-3y=31

subtract -y to -3y

-1-4y=31

add both sides by 1

-4y=32

divide both sides by -4

y= -8

substitute the value of y into an equation

7x= -1-(-8)

distribute

7x=7

divide both sides by 7

x=1

(1, -8)

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The 95% margin of error simony states that there is a 95% probability that the confidence interval contains the true population mean.

<h3>What is a margin of error?</h3>

It should be noted that the margin of error simply means a measurement that accounts for the difference between the actual result and the projected result in a survey sample.

In this case, the 95% margin of error simply states that there is a 95% probability that the confidence interval contains the true population mean. This is the radius of the 95% confidence interval.

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5 0
2 years ago
Three-quarters of a pound of candy cost 66 cents. Find the cost of one pound<br> of candy.
konstantin123 [22]

Answer:

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Step-by-step explanation:

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6 0
2 years ago
The half-life of a radioactive isotope is the time it takes for a quantity of the isotope to be reduced to half its initial mass
krok68 [10]
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7 0
3 years ago
A manufacturer of bolts has a​ quality-control policy that requires it to destroy any bolts that are more than 4 standard deviat
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Answer:

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Step-by-step explanation:

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3 years ago
I need help with the last two
Luba_88 [7]
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3 years ago
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