Отрезок BK- биссектриса треугольника ABC. Через точку K проведена прямая, пересекающая сторону BC к точке M так, что BM=MK. Докажите, что KM параллельно AB. 

Учусь в 7 классе и мне нужен ответ на уровне 7 класса, помогите пожалуйста!!!

   б)3х=-1 дробь 2    д)-5х=0    з)-4х= 8 дробь 25

Ребят, помогите. Все три кондиции используются. All Conditional Forms

1. (If / When) I leave work, I usually go to the fitness center to work out.

2. She hates TV. She thinks television is a waste of time. (If / When) she watches any television at all, it is usually a documentary or a news program.

3. My friend always keeps in touch by mail. (If / When) I get a letter, I usually write back immediately.

4. If I (have) enough money, I (go) on safari to Kenya. However, my bank account is empty!

5. I love to travel! When I (have) enough money, I (go) abroad. I do it almost every year.

6. I really wanted to go on safari to Kenya with my friends, but I couldn't afford to go. If I (have) enough money, I (go) with them.

7. I'm sorry, I didn't know you were allergic to chocolate. If I (know) , I (make) you a vanilla birthday cake.

8. Stop asking me what Amanda bought you for Christmas. Even if I (know) what she bought you, I (tell, not) you.

9. Nobody here speaks English. Too bad Gloria isn't here. If she (be) with us, she (can) act as our interpreter.

10. I am afraid I won't be able to come to your wedding next week because my company is sending me to New York to attend a trade show. I (miss, never) your wedding if I (have) a choice in the matter.

11. If the weather is nice tomorrow, she (walk) along the river to school.

12. If you help me move tomorrow, I (treat) you to a dinner and a movie.

13. If you were to help me move tomorrow, I (treat) you to a dinner and a movie.

14. If I were in Tahiti right now, I (snorkel) along a beautiful reef. I wouldn't be stuck here in this office with mountains of paperwork.

15. If Jerry hadn't stopped to pick up that quarter, he (cross) the street when the bus ran the red light. He might have been killed!

16. Tina's train arrived ahead of schedule. If I hadn't decided to go to the train station early, she (wait) there for more than twenty minutes before I arrived.

17. If I (pass) the test, I (get) an "A" in the class. Instead, I got a "C." I really should have studied more.

18. If I (be) rich, I (buy) that new Mercedes we saw yesterday. Unfortunately, I can't even afford a used car.

19. We (go) skiing this weekend, but there's no snow. Oh, well! We will just have to find something else to do instead.

20. If Heather spoke Chinese, she (translate) the email for you yesterday.

как взаимосвязаны предприятие и отрасль?