1) 21(18+х)=714 2) 16(4х-34)=608 3) 12(152+19х)=2052 4) (152х+32)*6=192

1) 21(18+х)=714 18+x=714:21 18+x=34 x=34-18 x=16 ========= 2) 16(4х-34)=608 4x-34=608:16 4x-34=38 4x=38+34 4x=72 x=72:4 x=9 =========== 3) 12(152+19х)=2052 152+19x=2052:12 152+19x=171 19x=171-152 19x=19 x=19:19 x=1 ============== 4) (152х+32)*6=192 152x+32=192:6 152x+32=32 152x=32-32 152x=0 x=0