Answer:
-1
Step-by-step explanation:
First find the inverse function. Rewrite the given function as
y = 5(x + 4) - 6 = 5x + 20 - 6 = 5x + 14
Second, interchange x and y:
x = 5y + 14
Third, solve this result for y:
5y = 14 - x, or y = (1/5)(14 - x)
This last result is the inverse function of the given f(x).
The value of this inverse at x = 19 is (1/5)(14 - 19) = (1/5)(-5) = -1
