Multiply the first equation by -1 to get -4x - y = --5
Then add the second equation 3x + y = 3
+ ____________
-x = -2 or x = 2
then plug in 2 for x in one of the equations and solve for y 4(2) + y = 5
8 + y = 5
Subtract 8 from both sides y = -3
So x = 2, y = -3 or (2,-3)
Using the z-distribution, it is found that a sample of 171 should be selected.
<h3>What is a z-distribution confidence interval?</h3>
The confidence interval is:
The margin of error is:
In which:
- is the sample mean.
- is the standard deviation for the population.
For this problem, the parameters are:
Hence we solve for n to find the needed sample size.
n = 170.7.
Rounding up, a sample of 171 should be selected.
More can be learned about the z-distribution at brainly.com/question/25890103
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Answer:
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Step-by-step explanation:
me me when I fought home him then
Answer:
6
Step-by-step explanation:
The 3 by 2 rectangle is 6 so 15-6=9
3 x (x-2) x 0.5 = 9
3 x (6-2=4) 4 = 12 / 2 = 6
4/7 of his money = $48
1/7 of his money = $48 ÷ 4 = $12
7/7 of his money = $12 x 7 = $84
Answer: $84