we know that
A relationship between two variables, x, and y, represent an inverse variation if it can be expressed in the form
or 
Let
x-------> the pressure in PSI
y------> the volume of the gas in cubic inches
In this problem we have the point 
so

Find the constant k

substitute the values of x and y


the equation is

therefore
<u>the answer is</u>

Answer:
x= -5/3
Step-by-step explanation:
Step 1: Simplify both sides of the equation.
7(5x+9)=12−(x+9)
7(5x+9)=12+−1(x+9)(Distribute the Negative Sign)
7(5x+9)=12+−1x+(−1)(9)
7(5x+9)=12+−x+−9
(7)(5x)+(7)(9)=12+−x+−9(Distribute)
35x+63=12+−x+−9
35x+63=(−x)+(12+−9)(Combine Like Terms)
35x+63=−x+3
35x+63=−x+3
Step 2: Add x to both sides.
35x+63+x=−x+3+x
36x+63=3
Step 3: Subtract 63 from both sides.
36x+63−63=3−63
36x=−60
Step 4: Divide both sides by 36.
36x/36 and -60/36
x= -5/3
Answer: your right answer is option 2