При каких значениях m и n уравнение (3m+5)x=4-2n  не имеет корней?

Вставьте глагол to be в Present Simple. 1. What ... your name? - My name ... Shirley Frank. 2. What ... your address? - My address ... 175 Grand Central Parkway. 3. What ... your phone number? - My phone number ... 718-1930. 4. Where ... you from? - I ... from New York. 5. I ... a pupil. 6. My father ... not a teacher, he ... a scientist. 7. ... your aunt a doctor? - Yes, she ... . 8. ... they at home? - No, they ... not at home, they ... at work. 9. My brother ... a worker. He ... at work. 10. ... you an engineer? - Yes, I ... .11. ... your sister a typist? - No, she ... not a typist, she ... a student. 12. ... your brother at school? - Yes, he ... . 13. ... your sister at school? - No, she ... not at school. 14. My sister ... at home. 15. ... this your watch? - Yes, it ... . 16. She ... an actress. 17. This ... my bag. 18. My uncle ... an office worker. 19. He ... at work. 20. Helen ... a painter. She has some fine pictures. They ... on the walls. She has much paper. It ... on the shelf. The shelf ... brown. It ... on the wall. Helen has a brother. He ... a student. He has a family. His family ... not in St. Petersburg, it ... in Moscow.

а может быть окончание ах?