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## High school geometry

### Course: High school geometry>Unit 2

Lesson 3: Properties & definitions of transformations

# Defining transformations

Given a description of the effect of a certain transformation, we determine whether that transformation is a translation, a rotation, or a reflection.

## Want to join the conversation?

• Sal is starting to use the phrase "maps to itself" a lot and the verb 'map'. In other words, what does Point O maps to itself mean at ?
• Mapping a point basically means to change the coordinates. Mapping is mostly used on the coordinate plane, where points can be transformed (or mapped) to another place. Now, to answer your initial question, "Point O maps to itself" means that when it is transformed using some kind of transformation (rigid or non-rigid), it maintains its original position on the coordinate plane. Hope this helps! :)
• What's a perpendicular bisector? Did I miss something in one of the videos or is that just new math language?
• Break it into the two words:
Perpendicular means intersecting at right angles
Bisector means cutting into two equal parts (so cutting a line segment in half)
So perpendicular bisector would be a line or line segment that is perpendicular to a line segment and cuts that line segment in half
• What does Sal mean by 'maps to itself?'
• A point is mapped to itself if it's in the same place before and after the transformation.
• I feel like I don't understand english anymore when I read these kind of problems xD
• What exactly is meant with 'the perpendicular bisector of segment PP'.
Any help would really be appreciated!
• bisect means cut in half, perpendicular is right angles, so it is a line or line segment which is at right angles to and divides the segment in half.
• Isn't it possible for the last example to be a rotation?
• Not with the information given to solve the problem.
• What does Sal mean when he says "maps to himself"? I noticed he used that phrase a few times...
• He is saying the point "maps to itself", which means the point stays in the same spot after it is transformed.
• i do not think this video helps me because i have to do the same thing in my lesson but there is no multiple choice answers