Video transcript
Identify all the rays shown in the image below. and this is a reminder what a ray is. A ray start at some point and then goes on forever in some direction. In order to find a ray you need that point that you're starting off on so let's that point over there is called X and then you need another point that sits on the ray and the ray is just keep going beyond, we will name that point as "Y" and we will call the ray "XY" It starts in "X" and keeps going in the direction of "y" for ever, it crosses "y" and keeps going further we need the second point to specify the direction in which the ray is going. So, lets identify all the rays shown in the image below, we can start anywhere, we will start at point J, the only line segment we have starting from J is JH going up, goes upto H and keeps on going in that direction beyond H, ray JH, starting from J going through H and going beyond it forever now if we go to H, there is no ray HJ as the line ends in J and does not keep going beyond J, there is no ray H as it is just one point, just usiing one point, we cannot say it as a ray. now looking at our diagram the only ray is JH. Now let us look at the other points. If we look at point C, once again there is no point after C to specify it as a ray, we can have a ray CE, starts at C goes through E and goes on for ever, you can also have a ray starting at C, going through F and going on forever, CE & CF are the same rays as F sits on ray CE and E sits of ray CF, so CE & CF are the same rays, now lets think about what we can do from point E, We can start at point E , go in the direction of C and go beyond C, so it is a ray, ray EC you could start in E and go in the direction of A and go beyond A, so EA is a ray, and we can start at E and go in the direction of F and go beyond F, that is ray EF ray EF and ray CF are different as the starting points are different Now lets go to point F. To the left of point F there is no other point. We can look at the right, we can have ray FE, start at F go through E and beyond E, you can have ray FC, start at F go through C and beyond C that is teh same thing as FE ray FE and ray FC are the same as the point E is on ray FC, then finally we have not focussed on point A you may think there is ray AE, but the line does not go beyond E, so it is not a ray, to the top of A there is no other point, so there is no ray there either that is all the rays based on the points specified. If they had given us a point over there, we could have had other rays, There are 6 rays in this problem
