Answer:
The Given function is
y= x + 10
To find the inverse of function , we use the following procedure
x=y-10
Now, replace x by y and y by x, we get the inverse of function
y=x -10 , is the inverse of the function, y=x+10.
As, it is given that inverse of f(x) is h(x)
Also, h(x)= 2 x - k-------(1)
Inverse of f(x)=x+10 is ,y= x-10, that is 2 y=2 x- 20------(2)
Comparing 1 and 2, gives
h(x)=2 y
-k=-20
k=20