1) 6х + х = 28; 7х = 28; х = 28/7; х = 4
2) 9х + 5х = 30 + 26; 14х = 56; х = 56/14; х = 4
3) - 3х - 6х = - 56 -7 ; -9х = -6 3; х = -63/(-9); х = 7
4) 0,9х + 0,4х = 4,3 + 7,4; 1,3х = 11,7; х = 11,7/1,3; х = 9
5) -1,6х - 0,3х = -1,8-5,8; -1,9х = -7,6; х = -7,6/(-1,9); х = 4
6) 3/8х - 7/12х = 24 - 19; 9/24х - 14/24х = 5; -5/14х = 5; х = -(5*14)/5; х = -14