Answer:
y=-2x+1
Step-by-step explanation:
y=Mx+b is the slope formula. You want to move y over to the other side to get the equation equal to y
Answer:

Step-by-step explanation:
There is a formula that can be used to find the x-value of the vertex of the parabola. This formula is 
We have the function 
From this function, we can find that

We can plug in our know values into the formula to get

Then we can plug in our x-value to find the y-value of the vertex

This means that the vertex would be 
Answer:
1.6 OR 8/5
(They are the same thing.)
Answer:
We have to find the 90% confidence interval for the mean
Given sample size
Sample mean
Population standard deviation
Here the confidence level is 90% then
And
The 90% confidence interval is
Here is the critical value at 0.05
From the tables
Now the 90% confidence interval is =
=
=(3840.44, 4133.56)
Hence the 90% confidence interval for the mean is (3840.44, 4133.56)