Предмет:
Другие предметыАвтор:
анонимПринимаем начальную скорость мотоциклиста равной х км/ч.
Поскольку скорость на обратном пути бала на 10 км/ч меньше, она составила: х - 10 км/ч.
Переводим разницу времени из минут в часы.
20 мин = 20/60 = 1/3 часа.
Получаем уравнение.
40 / (х - 10) - 40 / х = 1/3.
40 * х - 40 * х + 400 = 1/3 * х^2 - 3 1/3 * x.
1/3 * х^2 - 3 1/3 * x - 400.
x^2 - 10 * x - 1200 = 0.
D^2 = 100 - 4 * 1 * (-1200) = 4900.
D = √4900 = 70.
х = (10 + 70) / 2 = 80 / 2 = 40 км/ч.
Ответ:
Начальная скорость мотоциклиста 40 км/ч.
Автор:
bailey39Добавить свой ответ
Предмет:
Другие предметыАвтор:
анонимОтветов:
Смотреть
Предмет:
Другие предметыАвтор:
анонимОтветов:
Смотреть
Предмет:
Другие предметыАвтор:
анонимОтветов:
Смотреть
1 Read the Introduction. Which country did L.M. Montgomery come from? What do you know about this country? What are the most important cities? Which other places do people visit? 2 Find the words orphan and orphanage in your dictionary. Do you know any stories about an orphan? 3 Find these words in your dictionary. They are all in the story. What are they in your language? buggy carrot heart rude surprise After you read 4 What happens first? Number these 1-6. a Mrs. Lynde says unkind things about Anne. b Marilla takes Anne back to Green Gables. c Mrs. Spencer goes to the orphanage. d Anne says sorry to Mrs. Lynde. e Matthew meets Anne at the station. f Marilla and Anne visit Mrs. Spencer. 5 Are these sentences right or wrong? Change the wrong sentences. a The name of Mrs. Lynde's house is Green Gables. b Matthew is Manila's husband. c The color of Anne's hair is black. d Marilla asks Mrs. Spencer for an orphan girl. e Mrs. Blewett isn't very kind to her children. f Anne is rude about Mrs. Lynde's hair. Chapters 4-7 Before you read 6 Will Anne be happy at Green Gables? Discuss these questions, a How can Matthew and Marilla help Anne? b How can Anne help Matthew and Marilla? 40 7 Find these words in your dictionary. brooch cordial croup drunk island medicine minister slate vanilla wine Which word is it? a You can put this in a cake. b You take this when you are sick. c You can put this on a dress. d Children wrote on this in school. e These are drinks. f This makes children very sick. g You can find this person in a church. h You feel happy, and then sick. i There is water all around it. After you read 8 Answer these questions about the story. a Why does Anne tell Marilla a story about the brooch? b Why doesn't Anne want to go back to school? c Why is Mrs. Barry angry with Anne? d What mistake does Anne make with Mrs. Allan's cake? 9 Work with a friend. Student A: You are Diana. Ask Anne about Mr. and Mrs. Allan's visit to Green Gables. Student B: You are Anne. Tell Diana about the cake. Chapters 8-11 Before you read 10 What will happen next in the story? Discuss these ideas, a Anne will marry Gilbert Blythe. b Diana will marry Gilbert Blythe. c Anne will go away to college. d Matthew and Marilla will leave Green Gables. 11 Find these words in your dictionary. concert dye examination poem Which word goes with: a college? b music? c color?
прошу помогите по книге Anne of Green Gables LUCY MAUD MONTGOMERY Level 2
Предмет:
Английский языкАвтор:
ListerОтветов:
Смотреть