Answer:
The 98% confidence interval for the mean number of hours of study time per week for all students is (20.9, 25.1).
Step-by-step explanation:
Confidence interval:
Sample mean plus/minus the margin of error.
In this question:
Mean of 23.
Margin of error 2.1.
Then
23 - 2.1 = 20.9
23 + 2.1 = 25.1
The 98% confidence interval for the mean number of hours of study time per week for all students is (20.9, 25.1).
So the function is

the intial value is where x=0
where x=0, the value of f(0)=3
grouth is 1/3 but it is decay, so it might be correct, or not because it is decay
it is exponential decay
true it is a stretch of the funciton f(x)=(1/3)^x
when x=3, then f(3)=1/9
the true things are
The function shows exponential decay.
The function is a stretch of the function f(x) = (1/3)x .
Since x can't be zero (it sits at the denominator of the left hand side), let's split cases:
If x is positive
It this case, we can multiply both sides by x without changing the inequality sign:

But since we're assuming that x is positive, we can only accept the numbers between 0 and 1.
If x is negative
It this case, in order to multiply both sides by x we have to change the inequality sign:

But since we're assuming that x is negative, we can only accept the numbers which are smaller than -1.
So, putting all the pieces together, we have that the solution is given by the following interval:

Answer:
A. y=2x-9
B. 
Step-by-step explanation:
A. Parallel lines have the same slope. That means the line y=2x+3 has the same slope as any line parallel to it. So the slope is 2.
Using m=2, substitute it and (4,-1) into the point slope form and simplify to find the y-intercept.

B. Perpendicular lines have slopes which are negative reciprocals of each other. The slope of the line y=2x+3 is 2. The slope perpendicular to it is -1/2.
Using m=-1/2, substitute it and (4,-1) into the point slope form and simplify to find the y-intercept.
