# Math Help - Reflecting Graphs over Lines

1. ## Reflecting Graphs over Lines

I was wondering what I would do to the equation of any graph if I wanted to reflect it over a line, say x=k.

Merci

2. If $y=f(x)$ is the original function, then to reflect through $x=k$ then we must have $y=f(-x-k)$

3. I always find it best to work with an examples.

If you had a parabola y = x^2 reflected on x=2, substitute x for 4-x, so y = (4-x)^2
If you had a line y=x reflected on x=2, same thing as about , so y = (4-x)

Good luck!