За 15 !

вы­со­та, про­ве­дён­ная к ги­по­те­ну­зе, равна

произведению про­ек­ций ка­те­тов на ги­по­те­ну­зу
сред­не­му гео­мет­ри­че­ско­му про­ек­ций ка­те­тов на ги­по­те­ну­зу
сред­не­му ариф­мет­ри­че­ско­му про­ек­ций ка­те­тов на ги­по­те­ну­зу

найдите длину перпендикуляра kh, опущенного с некоторой точка k окружности на диаметр ab, если ah=3 см, bh=12 см.

окружность, вписанная в трапецию, точкой касания делит ее боковую сторону на отрезки 4 см и 9 см. найти радиус окружности.

в треугольнике abc с ∠a=90∘ и ac=4 см провели отрезок mk⊥ab , который делит сторону ab на отрезки 3 см и 5 см. найти mk .

6.5 см
2.5 см
5 см
3 см

Dear Frank,
I would like to tell you now I have resolved a conflict. The conflict was between me and my mother. I like sports, but my mus doesn't like when I spend lots of time doing sports. She has prohibited to go to my section. To solve this conflict, I was doing the following:
1. I have told my mum about benefits of sports
2. I have said that sport strengthens my health
3. I have shown a report card with good grades
4. I have promised to come home on time
5. I have spoken calmly and confidently
That day I could convince my mother that sport is a good thing. I hope my experience will be useful for your readers.
Best wishes,
имя без точки

Clare: There's Hansel and Gretel at the Unicorn Theatre. Would you like to see it on Saturday?
Marie: Great! I  have read  the tale but I  have not seen  the play yet.
Paul: It   was  on TV yesterday. I   enjoyed   it.
Melanie: I've got a Hansel and Gretel video and I  watched  it yesterday evening
Paul: Yesterday we   went  with our geography teatcher to the Natural History Museum. We   did  geography tasks and  were watching  dinosaurs for two hours. Have you been to the Natural History Museum yet?
Marc: No, we have not.
Paul: You should see the dinosaurs.Why not go there on Sunday?
Marc: That's great!