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Students, let's discuss isosceles triangles in greater detail in this video, we have already seen

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that an isosceles triangle is a triangle whose two sides are equal.

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So let me call side Ebb's X and side Acee as X.

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So these are of length X, say centimetre and side because of lengthwise centimeter.

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Now, this is an example of an isosceles triangle.

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We have also seen that the angles opposite the equal sides are equal.

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So in this case, Angle B is equal to angle C or we can see Angle ABC is equal to Angle HCB.

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All right.

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Now let's move on and understand some more interesting things about the isosceles triangle.

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Let me draw a B over here such that a B is the order of angle it.

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So is the angle by sector of angle.

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That means this angle over here is equal to this angle over here.

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Now, if that is true, then you will see that IPE is also the perpendicular by sector of B.C. and you

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will see that B is the median to B.C..

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Now let's see why that is.

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So over here you can see that triangle EPB is congruent to triangle ABC.

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That's this triangle A, B, B is congruent to triangle A, B, C, and you tell me why that is.

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So it's Asper as it is congruence criteria Y EP is equal to Eppy.

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That's a common sight.

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A B is equal to AC y because it's an isosceles triangle and it's given that these two sides are equal

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and and be a particular angle.

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C AP that's BNP is equal to Capri.

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Why is that.

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So it's Aspell construction.

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Right.

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AP is the angle by sector of angle.

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Therefore these two triangles are congruent and that gives us that this side let me call it a b b b

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B is equal to b c.

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Why.

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Because they are corresponding sites of congruent triangles.

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Similarly, you can see that this angle over here is equal to this angle.

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And let me try that over here.

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Angle EPB.

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Is equal to angle E, B, C, right, and they also are forming a linear pair, therefore angle B,

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B, plus angle ABC is equal to 180 degree because they are equal and there is equal to 180 degrees.

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So each of them has to be 90 degree to these two things together.

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Gives us that.

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AP is the perpendicular by sector of B.C., similarly, because BP is equal to B.C., we get that A

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B is the median to B.C..

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All right.

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Now, there's one more interesting thing you can note, because triangle A, B, B is congruently triangle

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ABC.

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Therefore, this area over here will be equal to this area over here.

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Therefore, this line that is AP is dividing triangle ABC into two parts of equal area.

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All right, so these are some interesting things that we have observed about isosceles triangles.