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Let's do this question in an equilateral triangle, ABC, it is an altitude now you can see in further

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videos that an altitude through a is a line that is drawn to a vortex and it is perpendicular to the

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opposite side.

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All right.

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Now, let's move on the question since then, for every square is equal to the four times it is square

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is equal to now.

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Pause the video, give it a try and then let's do it together.

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All right.

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We're back.

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Let's do it together.

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It's mentioned that triangle ABC is an equilateral triangle right there for every side is equal to eight.

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And this is an altitude.

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Therefore, this is a 90 degree angle.

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Now, in an equilateral triangle, the median and altitude coincide.

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Right?

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The median and the altitude coincide.

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Therefore, if it is the altitude, then it is also the median.

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Therefore, Beatty is equal to DC, which is equal to embittered.

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Now, why does this coincide?

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You can see that triangle a b the.

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Is congruent to triangle ADC.

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Why is that so we have this congruency, this side is equal to decide, this side is a common sight

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and you can see that.

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This angle is equal to 90 degree and this angle is equal to 90 degree, so it's just congruency, right?

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It's the right angle.

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Hypotenuse is equal and one side is equal.

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Therefore, these two triangles are congruent.

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If this is a 90 degree angle and hence really will be equal to D.C. and hence because B C is given us

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A and B is equal to D.C., we can arrive at Bery as a two.

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All right, now.

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Let's move on.

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Let me just put it down over here, bit congruent to ATC.

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All right.

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Now, Abdeh, is that right?

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Angle triangle, right?

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Because we dropped an altitude from it.

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So this angle over here is 90 degrees.

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Therefore, AB Square is equal to 80 square plus Biery Square as per Pythagoras's theorem.

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Right.

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Abey's the hypotenuse I put in a square is equal to the sum of the squares of the other two sides.

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That's what we have written over here.

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Now we know abs equal to eight.

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We know Beedie is equal to Ebeye two.

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Right.

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So let's write that over here.

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That's absolutely Ebbe and beauty values over here.

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So that's a square is equal to 80 squared plus Ebeye two the whole square which is equal to square by

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four.

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Now let's take a square by four to the other side and we get 80.

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Square is equal to square minus a square by four which is equal to three by four square.

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And let's take four over here.

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We get for 80 square is equal to three square.

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Right.

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And that gives us the answer.

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We have to find out for every square.

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Right.

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That's what is asked.

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That's equal to three a square.

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And in the options, you can see that B is given over here.

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Absolutely right.

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So this option is the correct answer because three square is the same as three square and four square.

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We have proved over here is equal to three square.