Final answer:
The formula for f^(-1)(x) for x = 20 is approximately 27.4, representing the number of years since the tiny house was built when the value of the tiny house is $20. In a real-world situation, the inverse function may not have a practical application.
Step-by-step explanation:
Part A:
To find the inverse function f^(-1)(x) for x = 20, we need to solve the equation f(x) = -100(x^2 - 750) = 20 for x. Let's do that:
-100(x^2 - 750) = 20
x^2 - 750 = -20/100
x^2 - 750 = -0.2
x^2 = 750 - 0.2
x^2 = 749.8
x = ±√749.8
Since x represents the number of years since the tiny house was built, we can take the positive square root:
x = √749.8 ≈ 27.4
Therefore, the formula for f^(-1)(x) for x = 20 is approximately 27.4.
Part B:
In a real-world situation, the inverse function may not have a practical application. In this case, f^(-1)(x) represents the number of years since the tiny house was built when the value of the tiny house is $20. This information might not be relevant or useful in most situations, so the inverse function may not be necessary to use.