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Let's do this question, what is the center of the circle?

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Find angle deep, B, that's B, B, B, this is the angle that we need to find given angle sees equal

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to 40 degree and angle déby be a B, that's include 30 degrees already.

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

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All right, let's do it together.

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Let's mark the information that's given.

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We know that this angle is 40 degrees and it's given that angle, Déby is equal to 30 degrees.

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All right.

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Now you can see that angle.

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B, it will be equal to angle, Betty.

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Right, because these are SUB-STANDARD by the same arc.

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Right.

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So Angle B, Ed, this angle over here will be equal to and will be.

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And we know this is 30 degrees.

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So this angle also will be equal to 30 degrees.

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All right.

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Now we know that angle, EBC, B, C, right.

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This angle over here will be 180, minus 30, minus 40.

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Right.

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Because EBC is forming a triangle triangle EBC is 180, minus 30, plus 40.

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That's equal to one one zero degrees.

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So let's get over here.

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OK, now you can see that angle, ABC, that's this angle over here from the linear pair with this angle

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over here, that's angle NBC right to this.

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Plus this should be 180 degrees.

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So I can see that angle, EBD 180 minus angle EBC.

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That's 180 minus one hundred and ten degrees, which gives you 70 degrees.

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Right at this angle over here will be 70 degrees.

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Now what about angle A, B, E and angle A, B?

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You will see that both of these angles that this angle and this angle over here are substandard by the

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same arc.

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Right, Tamani?

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Therefore, these two are equal.

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That's about equal to angle 80.

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And hence this angle over here is also equal to 70 degrees.

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All right.

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Now, let's continue.

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We know that angle, EDV angle E, the B, right.

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That will be 90 degrees because EBR is the diameter.

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And we know that the angle SUB-STANDARD by the diameter is equal to 90 degrees.

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With this angle over here is the right angle.

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And so you can see that angle.

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CDB is also 90 degrees, right.

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Because this angle that KDB and EDB form a linear pair.

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So this and this should add up to 180 degrees because this is ninety degrees.

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This angle over here also will be 90 degrees.

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All right, let's mark that, OK?

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Now you can see that angle, PTB, that's B B B is equal to 90 minus 70.

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Right.

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This whole angle is 90 degrees and this much is 70 or PDV.

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That's this angle over here will be 90 minus 70.

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That is equal to 20 degrees.

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All right.

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Now let's observe quadrilateral B, B, C, B, we know that the sum of the angles of a quarter has

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to be 360 degrees.

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Right?

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So if you add this angle, plus beauty C plus BBC plus B KB, you should get 360 degrees.

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So Angle DPB, which is the angle that we need to find out is equal to 360 minus one hundred and ten.

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Minus 40, minus 90.

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Plus 20.

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Right.

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So deep B this is the angle.

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Why is this 90 plus 20.

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Because we know that BDC is 90 and PTB we have found it is 20.

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Therefore angle BDC right angle PDC is equal to 90 plus 20.

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Now when you solve this, you will get the answer answers 100 degrees and that is your solution.