Răspuns :
[tex]\Big\{\big[(x\times7):2\big] +4\times 7\Big\} : 6 = 7 \\ \big[(x\times7):2\big] + 28 = 7\times 6 \\ \big[(x\times7):2\big] + 28 = 42 \\ (x\times7):2 = 42-28 \\ (x\times7):2 = 14 \\ x\times7 = 14\times 2 \\ x\times 7 = 28 \\ x = 28:7 \\ \boxed{x = 4}[/tex]