Răspuns :
4+4x4-y:4+(4+4):4=21
4+4x4-y:4+8:4=21
4+8-y:4+2=21
până ici știu
Răspuns:
Salutare!
4+4×4-y:4+(4+4):4=21
4+16-y:4+8:4=21
4+16-y:4+2=21
20-y:4=21-2
20-y:4=19
y:4=20-19
y:4=1
y=1×4
y=4
Verificare:
4+4×4-4:4+(4+4):4=
4+16-1+8:4=
4+16-1+2=
20-1+2=
19+2=
21
Succes!