### Video Transcript

In which line must triangle ๐น๐ท๐ฟ be reflected to map it onto triangle ๐น๐ถ๐ฟ?

Letโs start by highlighting triangle ๐น๐ท๐ฟ and triangle ๐น๐ถ๐ฟ. Hereโs triangle ๐น๐ท๐ฟ. And hereโs triangle ๐น๐ถ๐ฟ. In a reflection, every point is the same distance from the central line. And the central line is the line that is being reflected over.

Our points ๐น and ๐ฟ are not changing. Point ๐ท turns into point ๐ถ. Point ๐ท and point ๐ถ are the same distance from the line ๐น๐ธ. ๐ถ is four units away from the line ๐น๐ธ. And ๐ท is four units away from the line ๐น๐ธ. Because points ๐น and ๐ฟ lie on the central line, they wonโt change.

Triangle ๐น๐ท๐ฟ can be reflected over line ๐น๐ธ to produce triangle ๐น๐ถ๐ฟ.