Три мальчика: алеша, саша и никита сложились и купили палатку.никита заплатил 60%от ее цены, алеша-40%от оставшийся суммы, а саша последние 240 рублей.сколько стоила палатка?

VARIANT 1

1. It often (rain) on Sundays. a) rained b) rains c) will rain d) is raining

2. she usually write a letter? a) Is b) Do c) Will d) Does

3. She (leave) the school in 2010. a) Leaves b) Left c) Lefts d) Leaved

4. people go to Jupiter before the 22nd century? a) Does b) Do c) Will d) Did 5. I (not want) to go to the dentist yesterday. a) don`t want b) doesn`t want c) didn't want d) won`t want

6. I always (harry) to the bus stop. a) harried b) will harry c) harry d) harries

7. My brother (not make) breakfast every morning. a) Don`t make b) Doesn`t make c) Won`t make d) Didn`t make

8. he buy a new house last month? a) Will b) Does c) Do d) Did

9. They (come) here tomorrow. a) Came b) Comes c) Will come d) Are coming

10.Choose right translation: It takes me 10 minutes to get to the University. a) Дорога до Университета занимала у меня 10 минут. b) Дорога до Университета занимает у меня 10 минут. c) Дорога до Университета будет занимать у меня 10 минут.

11.John (to want) to go to the museum yesterday. a) wanted b) wants c) will want d) want

12.We (paint) our house next week. a) Paints b) Will paint c) Painted d) Are painting 13.Choose right tense: We will be at college tomorrow. a) Past simple b) Present simple c) Future simple

14.It (not be) very cold next week. a) Is not b) Was not c) Were not d) Will not be

15.Choose right order of sentence: we'll/ maybe /tonight /in/ and /stay/ television/watch. a) Maybe we'll stay in and watch television tonight. b) Maybe we'll watch in and stay television tonight. c) Maybe we'll television watch in and stay tonight. d) Maybe we'll stay and watch in television tonight.

1. Выполним сложение дробей (3y + 9)/(3y - 1) и (2y - 13)/(2y + 5) и из полученного уравнения найдем значение переменной у, при условии, что сумма дробей равна 2:

(3y + 9)/(3y - 1) + (2y - 13)/(2y + 5) = 2;

Приведем к общему знаменателю (3y - 1)(2y + 5):

(3y + 9)/(3y - 1) * (3y - 1)(2y + 5)/(3y - 1)(2y + 5) + (2y - 13)/(2y + 5) * (3y - 1)(2y + 5)/(3y - 1)(2y + 5) - 2 * (3y - 1)(2y + 5)/(3y - 1)(2y + 5) = 0;

Дробь равна нулю, если числитель равен нулю:

(3y + 9)(2y + 5)+ (2y - 13)(3y - 1) - 2 * (3y - 1)(2y + 5) = 0;

6y² + 15y + 18y + 45 + 6y² - 2y - 39y + 13 - 2(6y² + 15y - 2y - 5) = 0;

6y² + 15y + 18y + 45 + 6y² - 2y - 39y + 13 - 12y² - 30y + 4y + 10 = 0;

- 34y + 68 = 0;

- 34y = - 68;

y = 2.

Объяснение:

сумма дробей равна 2,если у=2