4. 1457 : (7 + 6х) = 47;
5. m + 6m – 5 = 72;
6. (24 – х) + 27 = 49;
7. 7у – 35 = 21;
8. 72 : (х + 3) = 12;
9. 487 + 17х = 589;
10. 138 + х + 57 = 207;
11. (28 – 9х) = 10;
12. (х + 15) ∙ 8 = 160; 15. 1457 : (7 + 8х) = 47;
13. 28 – (5х ¬– 11) = 12; 16. 96 : х = 12;
14. (х + 59) : 3 = 20; 17. 805 : (у + 26) = 23.