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Naming Points, Lines, and Planes

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Today I'm going to teach you how to name Geometric  Figures, specifically Point line and Plane. A point  

is very easy to name they just assign a letter to it. There's point A, there's point B very simple,  

but a line is a set of points that is  going in opposite directions. Now there's  

three points on there, but you use any two points on the line, you can name it line AB,  

or you could use a little symbol on top of there, the order doesn't matter it could be BA, AC, CA  

BC or AB, any two points, don't use three, don't use one. What about line segments. Well segment  

is just a part of a line it, doesn't keep going on forever, so there's no little arrows. Now this  

segment here could be called line segment AB or  you could just use a little symbol on top of there  

and again the order doesn't matter so it could be BA, but you have to name it with those end points.   

Now that's going to BC, or CB those  two endpoints or the whole line segment  

could be AC or CA, just use the end points. Planes can be a little more complicated.  

Now here we're going to have a plane, a set of points making up a two-dimensional surface and  

see that R right there does not represent a point, we can name the entire plane plane R. It's going  

to be cursive if they're going to do that, you  could also use any three non-co-linear points  

like plane ABC, non-collinear means they don't  make a straight line, I'll explain that later  

but again the order doesn't matter it could be BAC, or CBA, no big deal. Let's go ahead and try again.  

Now this plane could be named plane M, but it also has five little points on there we're going to  

use those, go ahead and name it, again that's plane M, here what can we name the plane if all  

the arrangements, all the different orders of the same three letters are treated as one name. Well  

let's go ahead and just go in order, let's go PQR, it could be named plane PQR just use the symbol  

but I'm gonna write all the ways that you could  start with just the letter P and I'll go in order,