Answer:
x=-8 y=6
Step-by-step explanation:
Add the two equations together. This cancels the x and gets us y=6
Then substitute y in more the first equation which gets us -8
Answer:
The value of the test statistic is 2.8.
Step-by-step explanation:
The test statistic is:

In which X is the sample mean,
is the value expected value for the population mean,
is the standard deviation and n is the size of the sample.
Sales at a fast-food restaurant average $6,000 per day
This means that 
Sample of 49
This means that 
The sample showed average daily sales of $6,400.
This means that 
Population standard deviation is about $1,000.
This means that 
The value of the test statistic is



The value of the test statistic is 2.8.
Answer: what math is this
Step-by-step explanation:
Answer: Approximately 1.9 atm
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Work Shown:

If the volume is 3.5 liters, then the pressure is approximately 1.9 atm.
Note the increase in volume leads to the reduction of pressure, and vice versa. The two variables have an inverse relationship.
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As a check,

We don't get the exact thing on both sides, but the two sides are close enough. We have rounding error due to P2 being not exact.
A more accurate check could be

which has the two sides much closer to one another. This helps us verify the answer.