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Tasks like this one are difficult for me. I have been looking at this task alone for a few hours now. enter image description here

g) The circle has the center at O. AB cuts of a 60 degrees section, while DE cuts of a 20 degree section.

The rest is just like this; bestem = find. Vis at = show that.

The only thing I see is that $\angle AOB$ is $60^\circ$ And from that there is a rule that should make $\angle ADB = 30^\circ$ But I'm not convinced that is correct. I can't find a word for that rule in english. Wiki gets complicated really fast about even simple stuff.

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    http://en.wikipedia.org/wiki/Inscribed_angle2012-05-28
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    There is such a rule. If you have a chord $AB$, and a point like $D$, then the angle subtended by $AB$ at the centre of the circle (that is, $\angle AOB$) is twice $\angle ADB$. Since $\angle AOB=60^\circ$, you are right in asserting that $\angle ADB=30^\circ$.2012-05-28
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    I think the use of words like "ass" should be avoided here.2012-05-28
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    Similarly, $\angle DAE=10^\circ$. That should give you plenty of information to chase down the rest.2012-05-28
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    I forget how dandy the U.S is compared to the UK. My bad. Thanks for the help @AndréNicolas2012-05-28

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