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I students, welcome to Triangles, let's get started discussing some of the basics of a triangle.

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Let's take an example.

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Over here we have Triangle, ABC and Triangle is a three sided figure.

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So three sides are there.

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You have A, B, B, C, and these are the three sides of this triangle.

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Remember, the triangle is a three sided polygon.

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You cannot have a polygon with two sides.

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All right, let's move on.

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It has three angles, you can see that the three angles are angle B, C, that's angle E, you can call

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it angle E also and you have Angle ABC.

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That's Angle B and you have Angle BCA, which is Angle C.

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All right.

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And this triangle over here has three.

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What is this.

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That's A, that's B and this is C, these are the three vertices of this triangle.

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And how do we know the triangle really know using this shape.

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This is Triangle ABC, that's how we call it.

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Now we will discuss various interesting properties about triangles so that you'll be able to solve any

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question that comes from triangles.

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Let's move on.

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Over here again, I take a triangle ABC now over here, we know that it has three sites, right?

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The side opposite angle, it is denoted with small letter E, the side opposite angle B is denoted with

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smaller the B and the side opposite Anglesey is denoted with small little C.

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Now remember A, B and C, these are lengths of these sites.

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Therefore, length of side B C is denoted as small letter M, length of side AC is denoted with small

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letter B and length of side A, B is denoted with small letters.

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See?

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Now, let me mark these angles as angle one angle to an angle three.

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Now, in a triangle, the angle opposite the greater side will be greater.

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But for example, over here you can see that A is greater than C, right?

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Remember, these are lengths, the A's of greater length than C, but what can we derive out of that

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based on this property?

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We can see that the angle opposite it, which is that angle that's capital a right or angle one that

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will be greater than angle opposite C, which is Anglesey or angle three.

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So we can find that angle one will be greater than angle three.