1) у×(58-27)=62
31у=62
у=62:31
у=2;
2) (5-x)×3=4x-6
15-3х=4х-6
-3х-4х=-6-15
-7х=-21
х=-21:(-7)
х=3;
3) (3+x)×5-3x=57
15+5х-3х=57
2х=57-15
2х=42
х=42:2
х=21;
4) (a+6719+5737)-(5610+2048)=4509+3492
а+12456-7658=8001
а+4798=8001
а=8001-4798
а=3203;
5) (196+79-y)+2999+1609=3007+1602
275-у+4608=4609
-у=4609-275-4608
-у=-274
у=274