Răspuns:
a = 416
Explicație pas cu pas:
168 - 8 ·[12 · 17 - 4· (a : 8:2)]:5 = 8 <=>
168-8 = 8 ·[12 · 17 - 4· (a : 8:2)]:5
160:8 = 20 = [12 · 17 - 4· (a : 8:2)]:5
12 · 17 - 4· (a : 8:2) = 20·5 = 100
204 - 4· (a : 8:2) = 100 =>
204-100 = 4· (a : 8:2)
4· (a : 8:2) = 104
a : 8:2 = 104:4 = 26 =>
a:8 = 26·2 = 52 =>
a = 52·8 =>
a = 416