Question

Which statement could be used to explain why f(x) = 2x – 3 has an inverse relation that is a function?

1. The graph of f(x) passes the vertical line test.
2. f(x) is a one-to-one function.
3. The graph of the inverse of f(x) passes the horizontal line test.
4. f(x) is not a function.

Answer 1

2. f(x) is a one-to-one function.

Explanation:

If a relation passes the vertical line test, it is a function.

If a relation passes the vertical line test and the horizontal line test, then it is a one-to-one function, and its inverse is also a function.

Answer: 2. f(x) is a one-to-one function.