А) 3(у-5)-2(у-4)=8
3у-15-2у+8=8
у=8-8+15
у=15
б) -5(5-х)-4х=18
-25+5х-4х=18
х=15+25
х=43
3684×826-56+528-7 = 3.043.449
20468÷2+56942-378×35838 = 13.479.588
2х -5 =х +1
2х -х =5 +1
1х =6
х =6 :1
х =6
проверка:
2 *6 - 5=6 +1
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