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3 years ago

Find the solution of equations -x+5y=30 10x-5y=-75

Mathematics

1 answer:

Kipish [7]3 years ago

8 0

Answer:

The solution set would be (-5, 7)

Step-by-step explanation:

To find the solution to the system. simply add them together. This will cause y to cancel and allow you to solve for x.

-x + 5y = 30

10x - 5y = -75

--------------------

9x = -45

x = -5

Now we can place that value into either equation and solve for y.

-x + 5y = 30

-(-5) + 5y = 30

5 + 5y = 30

5y = 35

y = 7

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σ = 4 minutes

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Confidence level = 95%

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Compute the critical value of z for α = 5% as follows:

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*Use a z-table.

Compute the sample size required as follows:

$MOE=z_{\alpha/2}\ \frac{\sigma}{\sqrt{n}}$

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