## Acute Right and Obtuse Angles

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In this video, I really wanted to introduce
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you to some terminology for some basic angle types
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and terminology. I wanted to introduce you to are
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acute angles, right angles, and obtuse angles.
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I think when we go through these,
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it will be pretty self-explanatory.
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And an acute angle is an angle --
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let me just draw them first
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then you might,
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you might,
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it might start to make sense.
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So an acute angle
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will look something like that.
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I draw two rays
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coming from a common point.
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I could also --
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so the acute angle could be this angle right over here.
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I could also draw an acute angle;
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maybe an angle that is formed from an intersection of two lines,
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so this angle would be acute,
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and so will this angle.
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They're both acute angles.
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We are going to see acute angles as ones
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that are --
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that since I haven't defined right angles yet.
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They are narrower,
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so we are going to see that they are
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smaller than right angles.
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Right angles are when the rays
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or the lines are going, oh
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I guess, I don't want to use the word "right"
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in my definition.
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They are kind of
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if one is going horizontal
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then the other one will be going vertical.
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so let me draw with rays first
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so the right angle
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this one is going from the left to the right
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and the other ray is going from the bottom
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to the top
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this angle right over here
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is a right angle
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and I could label it like that
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but the general,
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the general convention for labeling right angles
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is to put a little,
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a kind of a half of a box over there.
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That tells me that this is a right angle
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or, that if this is going left to right
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this is going perfectly top to bottom
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that this is a no way kind of
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that this is a completely,
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I guess the best way to think about it
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why it's called right
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is that this ray is completely upright
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compared to this ray over here
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let me draw with some lines
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if I have one line like this
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and I have another line like that
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a right angle over here
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actually all of these would have to be
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right angles
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it would mean that this line
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is completely,
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if this line were the ground,
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this line is completely upright
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relative to this line over here.
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so either these,
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so that is what a right angle means
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so now that we defined right angle
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I can give you another definition for acute angle
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so an acute angle has a measure
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or it's smaller than a right angle
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which are different ways to measure angles
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so you'll see that a right angle
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can be measured as 90 degrees
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this over here is less than 90 degrees
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so this is less than 90 degrees.
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and one way to conceptualize this is
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that this angle,
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it's opening is smaller
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it's more narrow,
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it's lines are,
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you would have to rotate one line
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less to get to the other line
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then you would over here.
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here, you would have to move
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all the way over there
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here you only have to move it a little bit
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so the acute angle is less than a right angle
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what an obtuse angle is
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it is greater than a right angle
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so let me draw a couple of examples
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of obtuse angles
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so an obtuse angle might look like
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let me get it a little clearer
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might look like that
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if it was a right angle,
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then this line over here
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would be,
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would look something like that
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it would be completely upright
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relative to this, if this were the ground.
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but we don't see that
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this orange ray over here is actually
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opened out wider
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it's opened up wider
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so it is obtuse.
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it is obtuse
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so this kind of comes from the actual
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everyday meaning
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acute means very sharp or very sensitive
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obtuse means not very sharp or not very sensitive.
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you could imagine this looks like a sharp point
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or it's, it's not opening up much.
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so maybe it's more sensitive to
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you know, relative to other things
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I don't know, just trying to make connections
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This is less sensitive
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It's all big and open
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It won't be able to notice things that are small
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or maybe that is not an appropriate analogy
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but one way to think about it
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it's kind of open up wider,
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or it's bigger than a right angle
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it's larger than 90 degrees
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larger than 90 degrees
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if you measure it
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you would have to rotate this ray more to
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get to this other ray
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than you would if you had right angles
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and definitively a lot more if they were acute angles.
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If I were to draw this with lines,
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which of the angles are obtuse and
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which are acute?
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Well the way I drawn them right over here,
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these two over here are acute
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are acute
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and then these over here are going to be
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obtuse
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so this one
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and this one
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these are both obtuse angles
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and I actually drew them up here as well.
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This one and this one are going to be
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obtuse
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so very simple idea
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if one line
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or if one ray is relative to the other one
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is straight up and down
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versus left to the right
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or is completely upright
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then we're talking about a right angle
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if they are closer to each other
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if you had to rotate them less
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you're talking about a acute angle
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if you had to rotate them more
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you are talking about an obtuse angle
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and I think if you look at them visually
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it's pretty easy to pick out
Title:
Acute Right and Obtuse Angles
Description:

The difference between acute, obtuse and right angles

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Video Language:
English
Duration:
05:32
 16chioue edited английски език subtitles for Acute Right and Obtuse Angles 16chioue edited английски език subtitles for Acute Right and Obtuse Angles 16chioue edited английски език subtitles for Acute Right and Obtuse Angles 16chioue edited английски език subtitles for Acute Right and Obtuse Angles 16chioue edited английски език subtitles for Acute Right and Obtuse Angles 16chioue edited английски език subtitles for Acute Right and Obtuse Angles 16chioue edited английски език subtitles for Acute Right and Obtuse Angles 16chioue edited английски език subtitles for Acute Right and Obtuse Angles

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