SOLUTION: if i have angles in the circle... how do i figure them out if i kno the arcs?

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Question 404376: if i have angles in the circle... how do i figure them out if i kno the arcs?
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
central angles (vertex at the center of the circle) are equal to their encompassed arc

vertical angles (lines intersecting in a circle) are equal to the average of the encompassed arcs

a special case of the vertical angle is when the vertex is on the circumference of the circle
___ in this case ; one of the encompassed arcs is zero
___ the measure of the angle is still the average of the arcs ; but the average is half of the remaining arc