Răspuns: x = 4
Explicație pas cu pas:
1 + { 2 × [ 3 + ( x - 4 ) × 5 ] : 6 } × 7 = 8
{ 2 × [ 3 + ( x - 4 ) × 5 ] : 6 } × 7 = 8 - 1
2 × [ 3 + ( x - 4 ) × 5 ] : 6 = 7 : 7
2 × [ 3 + ( x - 4 ) × 5 ] : 6 = 1
3 + ( x - 4 ) × 5 = 1 × 6 : 2 → aplic metoda mersului invers
3 + ( x - 4 ) × 5 = 3
( x - 4 ) × 5 = 3 - 3
( x - 4 ) × 5 = 0
x - 4 = 0 : 5
x - 4 = 0
x = 0 + 4
x = 4
