Răspuns:
[tex](z \div 8) + 18 = 7 \times 3 \\(z \div 8) + 18 = 21 \\ z \div 8 = 21 - 18 \\ z \div 8 = 3 \\ z = 3 \times 8 \\ \huge\boxed{ z = 24}[/tex]
