We are given a points (1,16).
First values of the coordinate represents x-coordinate and second values of the coordinate represents y-coordinate.
So, for the given coordinate (1,16), we have x-coordinate = 1 and y-coordinate = 16.
We are given expression y=f(bx).
Let us replace values of x and y in this expression, we get
y=f(bx).
16 = f(b*1).
16=f(b)
So, we got value of function f at b is 16.
We know, parent function is written in from y=f(x).
This time b got the position of x.
So, we could just say b=1.
