Answer:
x = -7
x = 4
Step-by-step explanation:
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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What exactly do you need help with with this topic<span />
We use y=mx+c we know that c= 4 A’s this is the y intercept . Next we need to work out the gradient(m). For every two squares along we go three squares up. This means are gradient is 1.5. Finally we input are values into the equation y=1.5x+4
Answer:
Step-by-step explanation:
Collect the like terms!
x-9x+8x+3-3
Now simplify,
-8x+8x+0
0+0
Answer = 0