The answer would be 309! I hope this helps!
Assuming you want the inverse of f(x)=x²-2,
f(x)=x²-2
repalce f(x) with y
y=x²-2
switch x and y
x=y²-2
solve for y
x=y²-2
x+2=y²
√(x+2)=y
replace y with f⁻¹(x)
f⁻¹(x)=√(x+2)
the inverse is √(x+2)
So since you gave all of the equations of everyone's amount that they put in, it saves some work.
Let's add up everyone's contribution and then solve for x:

Then since we know the television costs $2,000, we can set this expression equal to that and simplify terms. Then we can solve for x:



So since Ronnie put in 'x', we can say that Ronnie paid $70.
Since Mark put in '2x + 500', we can plug in 70 for x to find that Mark paid $640.
And since Lisa put in '650 + 2x + 500', we can plug in 70 for x again to find that Lisa paid $1,290.
Answer:
(0, 9), (0, 0), (0, 1)
Step-by-step explanation:
Hope it helps you in your learning process.