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Course: Class 10 (OD) > Unit 9

Lesson 2: Number of tangents from a point
Math
Class 10 (OD)
Tangents to a circle
Number of tangents from a point
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Segments tangent to a circle from outside point

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Problem

Angle A is circumscribed about circle O.
What is the length of AB―?
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi
units
A circle centered around point O. Segment C O and segment B O are both radii. There are tangent lines from points C and B on the circle, making segment C A and segment A B. The four lines create quadrilateral C O B A, where angle C A B is seventy-three degrees. Segment A C is four units. Segment C O is three units.