На берёзе сидели x птиц, что в шесть раз меньше чем на сосне. После того как с сосны улетели 15 птиц, а на берёзу сели 10 птиц, количество птиц на каждом дереве сравнялось. Сколько птиц было на берёзе и сосне изначально?

Помогите решить умоляю!!!!!!

Present perfect

Grade/level: 2ESO

by anaojer

7) They offered her a place at the archaeological course

1) He is going on a business trip next Monday

2) They can do nothing to improve the situation

3) We wont ask you to give one more lecture

4) We wont ask you to give one more lecture

5) They arrived at the station on time

6) Students mustn't use dictionaries at the exam

7) We are going to discuss only very important things at our meetings

8) Did they ask you tell this story again

9) Does this house belong to the mayor

10) They used to publish a lot of new books every year

11) Should they hold a conference at another place next time

12) They are reconstructing our local sports centre at the moment

13) They are going to build a new road here

14) My brother usually leaves for school at 8 am

15) The farmer was feeding the animals at thet time

принадлежит ли точка (-2;-1) прямой заданной уравнением 3х-2у+4=0