Răspuns:
a=b+17
(a+b):(a-b)=235 rest 0
a+b=235(a-b)+0
a+b=235a-235b
b+17+b=235(b+17)-235b
2b+17=235b+3995-235b
2b=3995-17
b=3978:2=>b=1989
a=1989+17=>a=2006
a = 17 + b
( a + b ) : ( a - b ) = 235
( 17 + b + b ) : ( 17 + b - b ) = 235
( 17 + 2 × b ) : 17 = 235
17 + 2 × b = 235 × 17
17 + 2 × b = 3995
2 × b = 3995 - 17
2 × b = 3978
b = 3978 : 2
b = 1989
a = 17 + 1989
a = 2006
