Question

The graph of y = f(x) contains point (-1, 7). The graph is stretched horizontally by a factor of k about the line x = 2. The point (-1, 7) is transformed to (-13, 7). The value of k is

Answer 1

You might want to look at this web site.

http://www.bmlc.ca/PureMath30/Pure%20Math%2030%20-%20Transformations%20Lesson%204.pdf

Answer 2

I know about this site and i've done the lesson, I know how to use stretch factor I'm just unsure how to determine it the other way around

Answer 3

Well the first x coordinate is 3 units from line 2. It then is transformed 12 units to the left. So k must be 12/3=4