Find the measure indicated. Assume that the lines which appear to be tangent are tangent. Part 4 NO LINKS OF ANY KIND
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The angle between the two tangents drawn from an external point to a circle and the angle subtended by the line segment joining the points of the contact at the Centre are complementary,

So,

15.) let the unknown angle be x

=》x + 55° = 180°

=》x = 180° - 55°

=》

16. let the unknown angle be n

=》n + 80° = 180°

=》n = 180° - 80°

=》

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