Math notes Look at angles for by two rays with the same endpoint Here's another way be sure the end point so when we draw the two rays we actually end up with an angle the section that between the two raises referred to as the interior of the angle and like inside and then I guess outer part would be the exterior of the egg rays that intersect at that common endpoint or refer to as the size of an angle is an angle has two side points at the two-way shares called the vertex so we have to contacts since the endpoint that is to raise share the two rays that make up the angle or the sides of the angle you have the interior because they referred to the interior points just be the points that are in between to raise and then the outer portion would be the exterior part of the angle and naming an angle there's a few different ways that we can do that I'm going to draw this diagram so just a little bit bigger but how we gain an angle first of all one way to name an angle is to use his vertex call this angle a symbol for angle basically just looks like an angle dangle the only time that you can use the vertex to maybe angle is if there's only one angle in the diagram that has angle a as it's vertex of if we took a look at a diagram like this here if I wanted you to name the large angle we could not call that angle P because technically there's actually three different angles in this diagram that have angled b as its vertex and this one there's only one angle so that's why we can use it to be aware of that we can't call any of these angles and will be so you don't know which angles that we're actually referring to another way to name an angle is if they give you some additional points when you put the angle symbol and we can name a point on one side of the angle name the vertex and then name a point on the other side so we can call this angle BAC it would be the same angle is angle c h so take a little bit of practice but looking at this angle sometimes people have trouble deciding which angle that we're actually dealing with sometimes it helps with you trace it to wear it the and then a and then see so that kind of helps us look at the angle that we're looking at for angle of see baby it's exact same angle so we can use the vertex to name an angle there's only one angle in the diagram that has that particular letter as his vertex we can use three letters where we name on one side the vertex has to be the middle letter and then the point on the other side and then in some cases they'll put a number and the interior of the angle there'll be no degree symbol but the reasonable looks like a little range of circle. no okay cuz remember there's three different angles in this diagram that for two other names for angle one we could call angle one angle JMK we could call it angle KMJ m so you could also call it angle km how about angle 2 what should we calling to KML or you can switch the order as well hey ml forget a point on one side vertex and then a point on the other side same thing as angle l m k alright questions on that all right the next part of this section deals with using a protractor to find the measure of an angle again we're generally not going to use a protractor you're going to just use information that we've learned in Geometry figure out measures of angles So eventually will make more sense when you get to some problems this protractor possible is very similar to the Brewer postulate basically set up a number line and I told us how to find the distance between two points on a number line so we know if we have two coordinates on a number line to find the distance is the absolute value of the difference of the coordinates we're kind of going to use that for hiding the measures of the angle in New Zealand protractor again this basically just sets up this ideal of chrome tractor I'm not sure how much experience you can with protractors just know that in a half circle we have 180 degrees so in a full circle we have 360 and on a protractor there's generally two sets of numbers so notice on the outside it goes from 0 to 180 and then on the inside it goes in the opposite direction where zero is on the right it goes to 0 to 180 it actually doesn't matter which set of numbers you use but you just have to be consistent in a given problem if you're using the outer set of numbers you have to use it to find the value of both rays. both parts very similar to finding the distance between two or vents on a number line you're going to take the absolute value of the difference of the coordinates so you're going to look to see where these Rays cross either just using the inside numbers or just the outside maybe you can decide and it's technically the absolute value of the difference of the coordinates now you work this out we should always be able to put zero on one ring which makes this kind of easy so zero if you notices on the inside here and this other Ray crosses at 125 before using the inside numbers maybe you want to make sure that you're consistent inside numbers so that is just 125 - 0 or 125 if you chose to use the outside numbers you would come up with the same answer for the outside numbers that would be 180 - 55 still comes out to be home in 25 Angle are those things are called Radiance you don't have to worry about that you can help her to retail now I talked about the fact that YouTube use a number inside the angle to name the angle but there's a little raise Circle and it's kind of hard to tell there's actually a little race Circle there we're not going to use that number to name the angle when we have that raised Circle that is the symbol for degrees so they're giving us the measure of this angle to be you will not use the 62 to detangle if you wanted to name this angle you have no choice to to call it angle a when they actually want you to find the measure of the angle they put a little m in front and that just stands for measure to measure of angle a is equal to 62 degrees all right? all right as far as new material that's all that I'm covered we're going to work on an