please help with geometry
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Answer : 50 degree
To find angle 1 , we apply outside angle theorem . Refer to the diagram attached below.
Measurement of arc EF=140 degrees
Measurement of arc GH = 40
Angle D = angle 1
Theorem says
[tex]angle D = \frac{arc(EF)-arc(GH)}{2}[/tex]
Now we plug in the values
[tex]angle 1 = \frac{140-40}{2}[/tex]
angle 1 = 50
Measurement of angle 1 = 50 degrees