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2 years ago

Solve for x and y (use elimination or substitution). Show work.

Mathematics

2 answers:

Olenka [21]2 years ago

8 0

Yap this is the answer

mihalych1998 [28]2 years ago

5 0

7x+3y-1 = 10x -7y+9 as vertical angles

7x+3y-1 + x = 180 as supplementary angles

So, we have system of equations:

7x+3y-1 = 10x -7y+9 (1)

7x+3y-1 + x = 180 (2)

1) Simplify equation (1)

7x+3y-1 = 10x -7y+9 -----> -3x +10y =10

2) Simplify equation (2)

7x+3y-1 + x = 180 -----> 8x +3y = 181

(-3x +10y =10)*8 ------> -24x+80y =80

( 8x +3y = 181)*3 ---------> 24x + 9y = 543

-24x+80y =80

+<u>24x + 9y = 543</u>

89y = 623

y = 7

5) -3x +10y =10

-3x + 10*7 =10

-3x +70 =10

-3x = -60

x=20

Answer : x=20, y = 7

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Kisachek [45]

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3 years ago

Suppose that at a state college, a random sample of 41 students is drawn, and each of the 41 students in the sample is asked to

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Answer:

The confidence interval for 90% confidence would be narrower than the 95% confidence

Step-by-step explanation:

From the question we are told that

The sample size is n = 41

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the critical value of $\frac{\alpha }{2}$ is $Z_{\frac{\alpha }{2} } =Z_{\frac{0.05 }{2} }= 1.96$

For a 90% confidence the level of significance is $\alpha = [100 - 90]\% = 0.10$ and

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given that other values are constant and only $Z_{\frac{\alpha }{2} }$ is varying we have that

$E\ \ \alpha \ \ Z_{\frac{\alpha }{2} }$

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The confidence interval is mathematically represented as

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Now looking at the above formula and information that we have deduced so far we can infer that as the confidence level reduces , the critical value reduces, the margin of error reduces and the confidence interval becomes narrower

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2 years ago

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