Reflection of a Point About a Line

Reflection of a Point About a Line

## Formula

For point $$(x_1,y_1)$$ and line:

$$Ax+By+C=0$$

its reflection is:

$$\left(x_1-\frac{2A(Ax_1+By_1+C)}{A^2+B^2},y_1-\frac{2B(Ax_1+By_1+C)}{A^2+B^2}\right)$$

## Usage

- Used to find the mirror image of a point about a straight line.