Learn about The Angle Game Video

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Learn about The Angle Game

Let’s play the angle game, so I’ve drawn this crazy figure here and I’m going to give you a couple of angles and then I want you to figure out another angle. So let me give you some angles, so let’s say that this angle up here, I’m sure I’m using the right tool. Let’s say this angle up here that is 56 degrees and then I also tell you this angle here, this angle here is a 115 degrees, 115 degrees. And what I would like you to figure out is this is the object, this is the object of the angle game, I want you to figure out what this angle is right here. If you are brave you can pause the video and try to figure out yourself, if you would like me to walk you through it and maybe if I give you a couple of steps then you pause it then you get the rest of it by yourself. But I will now show you how I would have solved this in the angle game. And you have all the tools necessary to already solve it and I want you to be able to be good at this because this is kind of like the key skill in the S A T, so let’s see. Oh, I didn’t give you a key piece so you’re probably saying Sal I can’t solve this and that’s probably you can’t because I haven’t given you key pieces of information. This line here and this line here so this line and this line, they’re parallel. See I’m telling you to solve it before giving you these key pieces of information. That means that they are parallel, so what can we do with this figure? So whenever I see these types of problems either like by playing the angle game or on say on the S A T, I just literally kind of figure out every angle that I can figure out and slowly try to make my way to the goal angle. So let’s see what we can figure out here, so I’m going to do this in blue green color anything that I can figure out. So this angle is 56 degrees right and these lines are parallel. This line here looks like a transversile, a transversile so what do we know about—well let’s see. Unless of course funding angle to this angle right here, well its this angle right and what do we know about corresponding angles or parallel lines when you have a transversile. That’s 56 degrees, 56 degrees right because corresponding angles are equal, we got a lot of other stuff, and we can figure out that this angle is 56 degrees but that probably wouldn’t have gotten us close to our goal. We could have—if that angle is 56 degrees and its corresponding angle is also 56 degrees. That would have gotten us closer to our goal. We could have figured out that this is a 180 minus 56 rights which is what, 124 degrees. That really would have helped us much but I’m just showing you, this are all things that you can do while playing the angle game. But anyway the first step I said well this are corresponding angles, so that’s 56 degrees, so let see. I need to figure out this angle right here, I know this one and they’re in a triangle right? You see this triangle, if only I knew this angle, if only I knew this angle. Can you figure out this angle? Well it is supplementary to this 115 degrees right, so this green angle and this purple angle is equals to a 180, so this is a 180 minus 115, so what’s that? A 180 minus this is 65 degrees, so what have you done so far? We just said well this are parallel lines so corresponding angles are equal, so this 56 degrees is equal to this 56 degrees and then we said well this green angle and this purple angle are supplementary so they have to add up to 180, so this is 115, so this is 65 which is just 180 minus 115 right and I think you might see where I’m going now. Now we know two angles of a triangle and if you know two angles of a triangle, what can we figure out about the third. Well we know the angles of the triangle add up to 180 right? So we know, lets call this X, we know that X plus 56 plus 65 equals 180, this is a 121 I believe, 121 right equals to 180 and then X is equal to lets see a 180 minus 120 is 60. X is equals to 59 degrees, there we go. We have accomplished our first goal in the angle game and there—let’s do a tougher angle problem. This maybe wont involve parallel lines, I just want to show you everything really just boils down to everything we’ve learned about parallel lines and triangles and angle adding up to each other, so this one involves a star. Let me draw a star, so put a line from there to there, draw a line from there to there and what do we know about this? We know that this angle is 75—oh boy I’m using the wrong tool. This angle is 75 degrees; we also know that this angle is 75 degrees. We know this angle here is 101 degrees and your mission in this angle game is to figure out this angle right here. What is this angle? And this is a good time to pause because I will now show you the solution. So look what we do here, so this angle will gee I just like to mess around and see what I can figure out, so if this angle here is a 101 degrees, what other angles can we figure out? We could figure out, well we could figure out this angle, we could figure out a bunch of angles, we could figure out that these are the colors for this are my figure out angles. So that’s a 101 then this is supplementary, that’s 79 degrees right? That’s also 79 degrees right because this is also supplementary. This angle right here is the opposite to it, so this angle right here is going to be 101 degrees. 101 degrees, what else can we figure out; well we can figure out this angle right because it’s supplementary and we can forget this angle. We can also figure out this angle because we see this triangle right here, this angle plus 75 plus 75 is going to equal to 180 right, so let’s call this angle B, B for blue. So B plus 75 plus 75 is going to equal 180 right and I’m just using this triangle right here, so B plus 150 is equal to 180 or B is equal to 30 degrees. So we are able to figure this out, now what would you do if I told you we are now ready to figure out this yellow angle? It might not be obvious to you, you have to kind of look at the triangle in the right way and the S A T will do this to you all the time, all the time and that’s why I’m testing you this way. Well let me give you a little hint, look at this triangle, obviously not ideal, not ideal color when we do it in red so it really stands out. Look at this triangle, I’m telling you the hardest thing about this problems is just looking at the right triangle and kind of seeing oh wow you know I actually can figure out something. Look at this triangle right here, we know this angle of it, it’s 101 degrees. We know this angle, we just figured it out, it was 30 degrees, so all we have left is just to figure out this yellow angle called X right? So X plus 101 plus 30 is equal to 180 degrees because the angles in the triangle add up to 180 degrees. So X plus 131 is equal to 180, X is equal to what? 49 degrees, there you go, we’ve done the second problem in the angle game. I think that’s all the time I have now in this video, on the next video maybe I’ll do a couple more of these angel game problems. See you soon.

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Let’s play the angle game, so I’ve drawn this crazy figure here and I’m going to give you a couple of angles and then I want you to figure out another angle. So let me give you some angles, so let’s say that this angle up here, I’m sure I’m using the right tool. Let’s say this angle up here that is 56 degrees and then I also tell you this angle here, this angle here is a 115 degrees, 115 degrees. And what I would like you to figure out is this is the object, this is the object of the angle game, I want you to figure out what this angle is right here.

If you are brave you can pause the video and try to figure out yourself, if you would like me to walk you through it and maybe if I give you a couple of steps then you pause it then you get the rest of it by yourself. But I will now show you how I would have solved this in the angle game. And you have all the tools necessary to already solve it and I want you to be able to be good at this because this is kind of like the key skill in the S A T, so let’s see. Oh, I didn’t give you a key piece so you’re probably saying Sal I can’t solve this and that’s probably you can’t because I haven’t given you key pieces of information. This line here and this line here so this line and this line, they’re parallel. See I’m telling you to solve it before giving you these key pieces of information. That means that they are parallel, so what can we do with this figure? So whenever I see these types of problems either like by playing the angle game or on say on the S A T, I just literally kind of figure out every angle that I can figure out and slowly try to make my way to the goal angle.

So let’s see what we can figure out here, so I’m going to do this in blue green color anything that I can figure out. So this angle is 56 degrees right and these lines are parallel. This line here looks like a transversile, a transversile so what do we know about—well let’s see. Unless of course funding angle to this angle right here, well its this angle right and what do we know about corresponding angles or parallel lines when you have a transversile. That’s 56 degrees, 56 degrees right because corresponding angles are equal, we got a lot of other stuff, and we can figure out that this angle is 56 degrees but that probably wouldn’t have gotten us close to our goal. We could have—if that angle is 56 degrees and its corresponding angle is also 56 degrees. That would have gotten us closer to our goal. We could have figured out that this is a 180 minus 56 rights which is what, 124 degrees. That really would have helped us much but I’m just showing you, this are all things that you can do while playing the angle game. But anyway the first step I said well this are corresponding angles, so that’s 56 degrees, so let see.

I need to figure out this angle right here, I know this one and they’re in a triangle right? You see this triangle, if only I knew this angle, if only I knew this angle. Can you figure out this angle? Well it is supplementary to this 115 degrees right, so this green angle and this purple angle is equals to a 180, so this is a 180 minus 115, so what’s that? A 180 minus this is 65 degrees, so what have you done so far? We just said well this are parallel lines so corresponding angles are equal, so this 56 degrees is equal to this 56 degrees and then we said well this green angle and this purple angle are supplementary so they have to add up to 180, so this is 115, so this is 65 which is just 180 minus 115 right and I think you might see where I’m going now. Now we know two angles of a triangle and if you know two angles of a triangle, what can we figure out about the third. Well we know the angles of the triangle add up to 180 right?

So we know, lets call this X, we know that X plus 56 plus 65 equals 180, this is a 121 I believe, 121 right equals to 180 and then X is equal to lets see a 180 minus 120 is 60. X is equals to 59 degrees, there we go. We have accomplished our first goal in the angle game and there—let’s do a tougher angle problem.

This maybe wont involve parallel lines, I just want to show you everything really just boils down to everything we’ve learned about parallel lines and triangles and angle adding up to each other, so this one involves a star. Let me draw a star, so put a line from there to there, draw a line from there to there and what do we know about this? We know that this angle is 75—oh boy I’m using the wrong tool. This angle is 75 degrees; we also know that this angle is 75 degrees. We know this angle here is 101 degrees and your mission in this angle game is to figure out this angle right here. What is this angle? And this is a good time to pause because I will now show you the solution. So look what we do here, so this angle will gee I just like to mess around and see what I can figure out, so if this angle here is a 101 degrees, what other angles can we figure out?

We could figure out, well we could figure out this angle, we could figure out a bunch of angles, we could figure out that these are the colors for this are my figure out angles. So that’s a 101 then this is supplementary, that’s 79 degrees right? That’s also 79 degrees right because this is also supplementary. This angle right here is the opposite to it, so this angle right here is going to be 101 degrees. 101 degrees, what else can we figure out; well we can figure out this angle right because it’s supplementary and we can forget this angle. We can also figure out this angle because we see this triangle right here, this angle plus 75 plus 75 is going to equal to 180 right, so let’s call this angle B, B for blue. So B plus 75 plus 75 is going to equal 180 right and I’m just using this triangle right here, so B plus 150 is equal to 180 or B is equal to 30 degrees. So we are able to figure this out, now what would you do if I told you we are now ready to figure out this yellow angle?

It might not be obvious to you, you have to kind of look at the triangle in the right way and the S A T will do this to you all the time, all the time and that’s why I’m testing you this way. Well let me give you a little hint, look at this triangle, obviously not ideal, not ideal color when we do it in red so it really stands out. Look at this triangle, I’m telling you the hardest thing about this problems is just looking at the right triangle and kind of seeing oh wow you know I actually can figure out something. Look at this triangle right here, we know this angle of it, it’s 101 degrees. We know this angle, we just figured it out, it was 30 degrees, so all we have left is just to figure out this yellow angle called X right?

So X plus 101 plus 30 is equal to 180 degrees because the angles in the triangle add up to 180 degrees. So X plus 131 is equal to 180, X is equal to what? 49 degrees, there you go, we’ve done the second problem in the angle game. I think that’s all the time I have now in this video, on the next video maybe I’ll do a couple more of these angel game problems. See you soon.

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