how to prove this?

logistic_guy said:
this is the question

Prove \(\displaystyle m\overset{\LARGE\frown}{AB} = 130^{\circ}\).

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What theorems are available to you? There is one that tells you the answer immediately. Or, a related theorem might require a step or two.

If you need to prove this theorem without already having a similar one, you could do so by drawing in the center and two radii, and focusing on the angles in the resulting figure.

But you know by now we're not just going to give you a proof. You need to do some thinking and share it with us.
 
logistic_guy said:
i'm thinking. can i prove it by using the theorem?
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I have to repeat: WHAT THEOREM(S) DO YOU HAVE AVAILABLE???

You use what you have. I intentionally didn't tell you what theorem I had in mind; I searched and found several versions. The version I think of first applies directly, as I said, making a one-line "proof"; other versions might make a two-line "proof". Almost certainly they are expecting something different. But I have no idea what, until you show the context as I asked you to.
 
if i have chord and tangent line, i use Tangent and Intersected Chord Theorem. can i say the answer \(\displaystyle 130^{\circ}\) acording to the Tangent and Intersected Chord Theorem.
 
logistic_guy said:
if i have chord and tangent line, i use Tangent and Intersected Chord Theorem. can i say the answer \(\displaystyle 130^{\circ}\) acording to the Tangent and Intersected Chord Theorem.
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That is probably the theorem I have in mind; unfortunately, different sources give different names to the same theorem, or the same name to different theorems, so I can't be certain! (I know it with no specific name, like here; I find it by your name here.)

But, as I said, it seems odd that they would give the answer and ask for a proof, when it's so easy to get that answer by direct application of one theorem! The whole thing seems odd to me.

But at least you can see that it is not a hard question. And sometimes people can be confused when a problem is so simple they don't even feel that they've done anything, much less answered correctly.
 
thank you Dr.Peterson. i just sometimes get confused when the answer need no work to be done
 
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