Răspuns:
a = 61
[tex](2 \times a - 15) \div 3 - 9) \div 6 = 52 \\ \\ (2 \times a - 15) \div 3 - 9) = 52 \times 6 \\ \\ (2a - 15) \div 3 - 9 = 312 \\ \\ (2a - 15) \div 3 = 312 + 9 \\ \\ (2a - 15) \div 3 = 321 \\ \\ 2a - 15 = 321 \div 3 \\ \\ 2a - 15 = 107 \\ \\ 2a = 107 + 15 \\ \\ 2a = 122 \\ \\ a = 122 \div 2 \\ \\ a = 61[/tex]