Using the given graphWhat is the values of x when f(x)= -6

Given
The graph,
To find:
The value of x when f(x)=-6.
Explanation:
It is given that,
From, the above graph it is clear that, at y = -6, x=5 and x=9.
Since f(x)=y.
Then f(x)=-6 at x=5 and x=9.
Hence, the values of x is 5 and 9.