Question

Please help with geometry

Answer 1

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  

$angle D = \frac{arc(EF)-arc(GH)}{2}$

Now we plug in the values

$angle 1 = \frac{140-40}{2}$

angle 1 = 50

Measurement of angle 1 = 50 degrees