Problem finding exterior angle

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In the discussion about finding angle DAC in triangle ABC inscribed in a circle, the user calculated angle BAC as 60 degrees based on the other given angles. They attempted to apply the theorem regarding angles subtended from the diameter but struggled to progress further. Other participants suggested using the theorem that opposite angles of an inscribed quadrilateral sum to 180 degrees, but the user expressed confusion about how to apply it. Ultimately, the user confirmed they found the solution, indicating the answer is 60 degrees as stated in their book. The conversation highlights the challenges of applying geometric theorems in problem-solving.
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Homework Statement


Triangle ABC has been inscribed in the circle with center o.E is the midpoint of arc BC.DE is the diameter.E is joined to A, B and C.D is joined to A . If angle ABC =72 degrees and angle ACB = 48 degrees,
find angle DAC.
(I have attached the diagram given in book although its not a very good one)

Homework Equations


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The Attempt at a Solution


In this one what i did was,
i found angle BAC =(180-72-48)= 60 degrees
then i tried to subtend angle from the diameter to get 90 degree on the circumference but it did not help.
and i found the other angles like angle BEA=48 degrees and angle DEC= 72 degrees by the theorem the a chord extend equal angles on the circumference. But i can't get any further than this .Please help.
the answer given in my book is 60 degrees.
If I am going wrong somewhere please do let me know.
Thank you.
 

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hi 1/2"! :smile:

use the theorem that opposite angles subtended from the same chord (ie opposite angles of an inscribed quadrilateral) add up to 180° :wink:
 
I think i have already done it.
can you please be alittle more elaborate?
thanks.:smile:
 
1/2" said:
I think i have already done it.
can you please be alittle more elaborate?
thanks.:smile:

i'm confused … if you've already done it, what's the problem?

and I've given you the full theorem … what is there to elaborate further? :confused:
 
I am really sorry to confuse you.:frown:
Could you give a more direct clue how to get the angle DAC?
and i am really sorry.
 
Thank you
but i have got it.
 
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