Предмет: Геометрия, автор: СуперБотан

2 задачи, напишите решение дано пожалуйста

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Автор ответа: nafanya2014
0
1 задача
Дано:ΔАВС, АВ=ВС
         АД - биссектриса,
         <АДС=150°
Найти: <A, <B, <C
Решение.
АВ=ВС , значит Δ АВС - равнобедренный, угол А равен углу С.
В треугольнике  АДС угол ДАС в два раза меньше угла С.
< ДАС + < ДСА + < АДС=180°
Сумма углов треугольника равна 180°
< ДАС + 2< ДAС + < АДС=180°
3<ДАС+150°=180°
3<ДАС=30°
<ДАС=10°

<А=<C=2<ДАС=20°
<B=180°-<A-<B=180°-20°-20°=140°

2 задача
Дано: Δ MPN,
         < P=40°,
         <M=60°
Найти <MNF
Решение
Угол РMN=30° так как биссектриса делит угол пополам
<MNP=180°-<PMN-<MPN=180°-30°-40°=110°
Углы MNP и MNF- cмежные. Их сумма равна 180°
<MNF=180°-110°=70°


 


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Edna's Weekend
This is Edna Shaw. She's a language student at London University, so she's got a
lot of university work to do during the week. In fact, she doesn't have any
spare time on weekdays. But when the weekend comes she tries to have a good time getting some exercise and fresh air and entertainment, too.
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small two-room flat in the town center. After lunch the girls play tennis or go for a run
out into the country. Edna's got a second-hand Volkswagen which she bought very
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Saturday afternoon is the time to play sport but in the evening the girls sometimes
go out to listen to a band. Bars are very much like clubs, the music is free and everything
is very relaxed. It's great to listen to some music and dance.
On Sunday the two friends have a nice quiet morning reading newspapers over a
cup of coffee. Sunday is the day when Enda goes to see her parents. They live in a nice
semi in a suburb of London. Enda drives there for brunch. (Brunch is breakfast and lunch combined. It's becoming very popular to have brunch at the weekend.) Brunch is a
good time for all the family. They get together and eat brunch. It's normally a huge meal.
You have all the breakfast things and all sorts of salads and chicken and pies and lots of
fruit. A lot of people go out to a restaurant for brunch. Not the Shaws ... they enjoy theirs
at home.
On Sunday evening Edna and Nancy quiet down a bit. They watch a little television
or, perhaps, have a little chat and share the impressions of the day. It's time to get ready
for Monday. So they usually go to bed early