Răspuns: x = 7
Explicație pas cu pas:
[ ( x + 3 ) × 3 + 3 ] × 3 + 3 = 102
[ ( x + 3 ) × 3 + 3 ] × 3 = 102 - 3
[ ( x + 3 ) × 3 + 3 ] × 3 = 99
( x + 3 ) × 3 + 3 = 99 : 3
( x + 3 ) × 3 + 3 = 33
( x + 3 ) × 3 = 33 - 3
x + 3 = 30 : 3
x = 10 - 3
x = 7
