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Let's do this question in the figger B.C. is equal to be able to see every angle, B.C. is equal to

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40 degrees.

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Find Angle Beida.

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All right, let's model the given information.

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We have BK's, 40 degrees.

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We know that because equal to B and C, D battling to be all right.

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Now 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 are back.

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Let's do it together over here.

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It's given that BK's equal to a B, right.

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Therefore, Angle BCA will be equal to angle B C, that's equal to 40 degree Y because C, B is forming

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an isosceles triangle.

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And we know that angles opposite equal sites in an isosceles triangle are equal already.

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So we have found that angle.

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BSI is equal to 40 degrees.

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Now it is given that AB is parallel to C, right?

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Let me write that over here about parallel to city, therefore angle BSE will be equal to ÀNGEL, right,

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because these are alternate interior angles, but this angle over here will be equal to this angle over

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here, right.

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Abey's parallel to Kitty and he is acting as the transposon.

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Now we found that this angle is 40 degrees.

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Therefore Angle ACD also is equal to 40 degrees.

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All right.

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So this is also 40 degrees.

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Now you can see that BCT is a cyclic quadrilateral, right?

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Why is that so?

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B, C, D, and the all the vertices are on the circle, so BCD is a cyclic quadrilateral and we know

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that in a cyclic quadrilateral, opposite angles are supplementary, right?

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Obesity plus B is equal to 180 degree.

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Now or here, BCT is 40 plus 40, right, but that's 80 degrees, therefore you can find that angle

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beauty is 180 minus 80.

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That gives you the answer is 100 degree.

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And that is your solution.