Răspuns :
( x × 9 + 7 ) - 72 : 6 = 103
( x × 9 + 7 ) - 12 = 103
( x × 9 + 7 ) = 103 + 12
( x × 9 + 7 ) = 115
( x × 9 ) = 115 - 7
x × 9 = 108
x = 108 : 9
x = 12
( 12 × 9 ) + 7 - ( 72 : 6 ) = 108 + 7 - 12 = 115 - 112 = 103
a × 9 + 7 - 72 : 6 = 103
a × 9 + 7 - 12 = 103
a × 9 + 7 = 103 + 12
a × 9 + 7 = 115
a × 9 = 115 - 7
a × 9 = 108
a = 108 : 9
a = 12 => numărul