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In this video, let's learn how can we establish whether two given triangles are similar or not?

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Now, there are two rules which we can use to establish whether two triangles are similar.

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That's the a rule and the is rule.

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Now, this says rule is different from the test for congruency.

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Let's eat.

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Let's start with the rule or here.

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This rule states that if two angles of a triangle are equal to two angles of another triangle, then

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the two triangles are similar.

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Let's try to understand it.

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Over here we have two triangles.

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Let this angle be equal to this angle and let this angle be equal to this angle.

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So there are two sets of equal angles.

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Therefore, as per the error rule, these two triangles are similar.

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That is, these two triangles will have the same shape, but not necessarily the same size.

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All right.

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Now let's move on to the SARS rule.

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The SARS rule states that if two ratios of corresponding sides are equal and the included angles are

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equal, then the two triangles are similar.

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All right.

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So there are two criteria over here, two ratios of corresponding sites.

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That's what this is and this stands for.

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So over here, this stands for ratio of corresponding sites.

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And this is also stands for ratio of corresponding sites and this is stands for the included angle.

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And that one has to be equal.

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All right.

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Let's try to understand it with an example.

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Let me Marty, vertices of these triangles as ABC and BQ are now over here.

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Let's take two corresponding sides to be equal.

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That is A, B divided by P, Q, right.

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This ratio should be equal to let's take a C divided by P, R and B include an angle over here between

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this site and decide exactly.

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And the included angle between this site and this site is angle P.

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So the criteria is everybody p q is equal to AC by fiat that stands for the two is right and angle is

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equal to angle B.

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That's the included angle has to be equal between these sites.

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Now if that is true, then we can see that triangle.

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ABC is similar to triangle pick you up.

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So let's quickly revise.

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We have learned to criteria's which we can use to check whether two given triangles are similar or not.