13,17-2.[2x-3]=3 15,315-5.[2x+16]=115 17,20-[7.[x-3]+4]=2 19,[[6x-39];3].28=5628
2.[2x-3]=17-3 5.[2x+16]=315-115 7.[x-3]+4=20-2 [6x-39];3=5628;28
2.[2x-3]=14 5.[2x+16]=200 7.[x-3]+4=18 [6x-39];3=201
2x-3=7 2x+16=40 7.[x-3]=18-4 6x-39=201.3
2x=7+3 2x=40-16 7.[x-3=14 6x-39=603
2x=10 2x=24 x-3=2 6x=603+39
x=5 x=12 x=2+3 6x=642
x=5 x=642;6
x=107