I solved it this way , hope it’s correct ;)
Answer: 
Step-by-step explanation:
Given

We can write it as

Express x in terms of y

Replace y be x to get the inverse

To prove, it is inverse of f(x). 

So, they are inverse of each other.
X=the missing value
the median is the middle number, but in this case there are two which happens to be 25 and x
so the formula is
25+x/2=31.5
use algebra to solve
25+x=63
x=63-25
x= 38
Therefore, the missing value is 38.
Hope this helped. Let me know if you have any further questions:)
Answer:
PV= $40,279.36
Step-by-step explanation:
Giving the following information:
Number of periods= 8*12= 96 months
Interest rate= 0.039/12= 0.00325
Future value (PV)= $55,000
<u>To calculate the initial investment, we need to use the following formula:</u>
PV= FV/(1+i)^n
PV= 55,000 / (1.00325^96)
PV= $40,279.36
The perpendicular bisector of the segment passes through the midpoint of this segment. Thus, we will initially find the midpoint P:

Now, we will calculate the slope of the segment support line (r). After this, we will use the fact that the perpendicular bisector (p) is perpendicular to r:


We can calculate the equation of
p by using its slope and its point P: