Question 1075999
To solve (b), first solve for x in terms of y, or f(x):
y = (x+7)^2 -> x+7 = sqrt(y) -> x = sqrt(y)-7
Now swap x and y:
y = f^-1(x) = sqrt(x) - 7
We see from the graph that the original function and its inverse are 
symmetric about the line y=x, as they must be.
{{{graph(300,300,-6,20,-6,20,(x+7)^2,sqrt(x)-7),x}}}