Let's do this question, a bizarre tangent to the circle.
Is a second that is extended to be all right.
So this is a straight line.
Angle C is 30 degrees angle ACB is 70 degrees.
The question is find angle C or D.
All right.
So we have this angle as 30 degrees and this angle as 70 degrees.
Now, pause the video, give it a try and then let's do it together.
All right.
Let's do it together now, because this angle over here is 30 degrees.
Therefore, Angle AC DC also will be 30 degrees.
Right.
I suppose he can dungen theorem.
Right, because this is the angle formed by the tangent and AC, which is the second.
Therefore this angle over here, which is also subtenant by AC, will be equal to this angle over here.
Right.
So AC is equal to 30 degrees already.
Now what about angle A, C, D?
Because this is a straight line, right.
Therefore this angle and this angle together form 180 degrees.
Right.
Therefore, Angle A.D. is 180 minus 17.
That's equal to 110 degrees.
All right, let's model over here and we can have a C a D, right.
What would be this angle?
You know, that A.D. forming a triangle.
So angle C 80 will be 180, minus hundred and ten.
Minus 30.
Right.
But that is equal to 40 degrees, so you have this angle over here as 40 degrees.
Now we need to find angle codi angle see or you can see that angle.
What is the measure of ArchCity right now?
That would be double the measure of the angle SUB-STANDARD by this arc.
Now angle see, it is supported by side and we have found that the measure of that is 40 degrees.
Therefore Anglesey already will be two times 40, which is equal to 80 degrees.