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In this video, let's discuss the Essence's criteria to check whether two given triangles are congruent

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or not.

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All right, let's start with this.

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Your given triangle, ABC, and you're asked to draw a copy of it.

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All right.

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So this is Triangle ABC, and whoever is telling you to draw a copy tells you that side AC is seven

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centimetre side, ABC is six in the middle and side B, C is five centimeter.

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Is this information sufficient to draw a copy of ABC without any ambiguity?

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Let's try it.

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Let's make a statement, if you know the three sides of the triangle, you can draw a copy.

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All right, let's experiment whether this is true, but I have BCS equal to five centimeter.

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So let me draw a line because you sense that it's a five centimetre length.

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All right.

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Now, it's given that a B is of six centimetre, right?

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It's six centimeter.

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So let me take my compass, put the sharp edge at point B and draw and are such that the radius of the

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compass is six centimeter.

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All right.

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Now, similarly, let me take my compass or the sharp edge at point.

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Q And draw an arc over here such that it cuts the previous arc and let the radius of the compass at

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this time be seven centimeter.

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So I do it over here like this.

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Now these two arcs intersect at that point.

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Let me join that point with Q and B, do I do that like this?

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And similarly I do that over here.

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All right.

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Now, let me mark this point, as are you can see that if I have three sides of a triangle, I can draw

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a copy of it without any ambiguity.

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This is what we call the essence's criteria of congruence.

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Let's quickly repeat it.

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If you are given the three sides of a triangle, you can draw a copy of it.

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And there is no ambiguity.

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That is, there is only one shape in the form of a triangle where the three sides will be as per the

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given length.

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There won't be a case where you can draw two triangles, two different triangles, such that the three

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sides are as part of the given length.

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Therefore, if you know that the three sides of a triangle are equal to the corresponding three sides

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of another triangle, then they are congruent.

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Let's take an example over here you have triangle and here you have another triangle.

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Say it's given that this side is five centimetre, this is six centimetre and this is four centimetre

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and C for this triangle, it's given that this side is six centimetre, this is five centimetre and

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this is all centimetre then because there are two sides which are equal.

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So this side is equal to decide.

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This side is equal to this side and this side is equal to this side.

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So there are three sides are equal to corresponding three sides.

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Therefore, we can conclude that these two triangles are congruent.