SOLUTION: AD and DB are tangents to the circle and BC is the diameter. If angle ADB = 110 degrees, find angle ACB and give your reasons

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Question 1105836: AD and DB are tangents to the circle and BC is the diameter. If angle ADB = 110 degrees, find angle ACB and give your reasons
Answer by greenestamps(13209) About Me  (Show Source):
You can put this solution on YOUR website!


Let x be the degree measure of minor arc AB; then the degree measure of major arc ACB is 360-x.

The measure of angle ADB is half the difference between the measures of arcs ACB and AB:
110+=+%28%28360-x%29-x%29%2F2
110+=+%28360-2x%29%2F2
110+=+180-x
x+=+70

The measure of arc AB is 70 degrees.

The measure of angle ACB is half the measure of arc AB; half ot 70 degrees is 35 degrees.

The measure of angle ACB is 35 degrees.