36: (х 4)=9 92-(7+х)=43 (х-32)+13=9 (х+11)-40=21 (х+8): 4=120 28: (80: х)=7 (15*х)-12=18 21+(32-х)=63

1)36: 4х = 9;  4х = 36:9 = 4; х = 1;
2) 92 - (7+х) = 43; 7 +х = 92-43 = 49;  х = 49 - 7 = 42; х = 42.
3)(х - 32) +13 = 9;    х = 32+9 - 13 = 28;
4)(х+11) - 40 = 21;   х = 40 - 11 +21 = 50;
5)(х+8) : 4= 120;   х+8 = 120 х 4 = 480; х = 480 - 8 = 472;  х = 472.
6) 28 : (80 :х) = 7;  80 : х  = 28 : 7 = 4;  х =  80 :4 = 20; х = 20.
7) (15х) - 12 = 18;  15 х = 18 +12 = 30; х = 30:15 = 2; х = 2.
8)21 + (32-х) = 63;  32 - х = 63 - 21 = 42; - х = 42 - 32 = 10;  х = - 10.