Tangent to a Circle

This item is taken from IGCSE Mathematics (0580) Paper 31 of May/June 2012.

To deal with this item, let us summarize the details of the problem:
   (a) Syllabus area: Geometry
   (b) Specific topic: Angle Properties of Circles (Tangents)
   (c) Formula Needed: 

Another concept that we need to recall for this item is

Now, let us answer each of the questions. Let us start with a

Now, let us find the answer for b

Finally,

To summarize all the answers:

If you are interested on the derivation of the sum of the angles of a triangle, click here.

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