HELP! GEOMETRY!
in the accompanying diagram, line AB and line AC are tangents to the circle O, and chord BC is drawn, If the measure of the angle ABC is 72 what is the measure of angle A?

Question

HELP! GEOMETRY!
in the accompanying diagram, line AB and line AC are tangents to the circle O, and chord BC is drawn, If the measure of the angle ABC is 72 what is the measure of angle A?

96mertcank96 · Answer

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96mertcank96 · Answer

@thomaster  can i get some help please?

96mertcank96 · Answer

@phi

phi · Answer

There are a few ways to get the answer.
one way is draw in the radius OB and OC  to form 90 angles
now you can figure out the angle BOC

or note that the "inscribed angle" ABC is ½ the central angle BOC

either way you get BOC= 142
now use "4 angles of a quadrilateral" add up to 360

phi · Answer

**either way you get BOC= 144

96mertcank96 · Answer

after i get 144 for the angle boc what do i do?

phi · Answer

fill in the details
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