Предмет: Алгебра, автор: fg1531

Из одного пункта в другой, расстояние между которыми 120км, выехали велосипедист и мотоциклист. Скорость мотоциклиста на 10км/ч Больше скорости велосипедиста, поэтому он затратил на путь на 6 ч меньше. Какова скорость мотоциклиста?? ?

С полным решением

Ответы

Автор ответа: теоретик5

12

Ответ: 20 км/ч.

Объяснение: Пусть х км/ч скорость мотоциклиста, тогда скорость велосипедиста х-10 км/ч. Время за которое мотоциклист затратил на весь путь $\frac{120}{x}$ часов, а велосипедист $\frac{120}{x-10}$ часов. Разница во времени составила 6 часов. Составим уравнение:

$\tt\dispaystyle\frac{120}{x-10} -\frac{120}{x} =6\\120x-120(x-10)=6(x^{2}-10x)\\x^{2}-10x-200=0\\D=900$

х₁=(-10) (км/ч) не подходит, т.к. скорость не может быть отрицательной.

х₂=20 (км/ч) скорость мотоциклиста.

Предыдущий вопрос

Следующий вопрос

Похожие вопросы

Предмет: Русский язык, автор: кристина1838

помоги пожалуйста лайк поставлю пожалуйста

1 год назад

Предмет: Беларуская мова, автор: angel218

паставиць канчатки.Няма сшытка,зайца бензин…,даждж…, тралейбус…, яблык…, верх…, прастор… ,гараж… , трактар…, мед… .

1 год назад

Предмет: Английский язык, автор: Arsen1803

The Bolshoi theatre is famous for?

1 год назад

Предмет: Химия, автор: amira9773

1. Какие органические соединения называются аминокислотами?

7 лет назад

Предмет: Английский язык, автор: eguelus1

Помогите пожалуйста сделать тест:

1. We went to the museum and then had lunch ____________ the cafeteria.

1. in 2. on 3. at 4. to

2. Look! You have mud __________ your shoes.

1. in 2. on 3. at 4. to

3. They went _________ the restaurant and ordered their favorite tomato soup.

1. in 2. on 3. at 4. to

4. Can we meet __________ the morning before our classes start?

1. in 2. on 3. at 4. to

5. It says _______ the newspaper that they are getting married ___________ the spring _________ a small

church ___________ the island of Santorini.

1. in 2. on 3. at 4. to

6. There I was, sitting __________ the waiting room when who do you think came?

1. in 2. on 3. at 4. to

7. __________ Tuesday morning, I am going to the bank.

1. in 2. on 3. at 4. to

8. The coffee's on the table and there's some sugar __________ the cupboard if you want some.

1. in 2. on 3. at 4. to

9. The film starts ___________ 8 o'clock and I'd like to arrive by the start of the film.

1. in 2. on 3. at 4. to

10. I saw Jessica on Friday afternoon and she told me she's still ___________ university.

1. in 2. on 3. at 4. to

1. The defendant didn't _____________________ , even though everyone knew he was guilty.

1. confess

2. accomplish

3. persevere

4. manipulate

2. Tell me, is the situation _________________________ or temporary?

1. heritage

2. occasion

3. mutual

4. permanent

3. I don’t ___________________ of smoking, but I believe in the freedom of choice.

1. exhaust

2. accomplish

3. approve

4. distinguish
4. A book that has a _______________________ cover may sell better than a book with a blank one.

1. embarrass

2. benefit

3. conspicuous

4. beneath

5. Saying the wrong thing at the wrong time can really ______________ you.

1. distinguish

2. manipulate

3. embarrass

4. approach

6. The dolphins disappeared ________________the waves.

1. exhaust

2. anxiety

3. permanent

4. beneath

7. We want you to get maximum _______________________ from the course.

1. benefit

2. manipulate

3. approve

4. accomplish

8. The factor that ___________________ this company from the competition is customer service.

1. perseveres

2. distinguishes

3. confesses

4. embarrasses

9. The fear of unemployment can be a source of deep ____________ to people.

1. benefit

2. conspicuous

3. anxiety

4. occasion

10. He _________________with his task until he had succeeded in collecting an armful of firewood.

1. persevered

2. heritaged

3. collapsed

4. approached

11. He'd ________________ himself carrying all the boxes upstairs.

1. distinguished

2. accomplished

3. embarrassed

4. exhausted
12. I've seen Jana with them on several ________________.

1. occasions

2. approaches

3. heritages

4. collapses

13. I'm living with my parents, but it's only ______________.

1. heritage

2. temporary

3. exhaust

4. nutrition

14. ________________ respect is necessary for any partnership to work.

1. temporary

2. mutual

3. conspicuous

4. permanent

15. _________________ and exercise are essential to fitness and health.

1. heritage

2. anxiety

3. confess

4. nutrition

7 лет назад