Which function has an inverse that is a function? b(x) = x2 + 3 d(x) = –9 m(x) = –7x p(x) = |x|

The answer is m(x) = -7x =A function will only have an inverse function if the function is one-to-one. If you graph the function out and it passes the horizontal line test, it is one-to-one. Only the function m(x) = -7x will have an inverse that is a function. The graph of y = m(x) is a linear function. Linear functions pass the horizontal line test (it's symmetric about the y-axis). The function does not have an inverse that is a function because the graph of b(x) is parabolic. It will fail the horizontal line test when you graph it out. The function does not have an inverse that is a function because the graph of d(x) is a horizontal line. A horizontal line fails the horizontal line test because it is a horizontal line. The function does not have an inverse that is a function because the graph of p(x) fails the horizontal line test (it's symmetric about the y-axis).

i believe the correct answer is b.