m-9n/n+n/m m/n=1/3 помогите решить

( m - 9n ) / n + ( n / m ) = ( m( m - 9n ) + n^2 ) / mn = ( m^2 - 9mn + n^2 ) / mn m / n = 1/3 n = m : 1/3 n = 3m ( m^2 - 9m•3m + 9m^2 ) / 3m^2 = ( - 17m^2 ) / 3m^2 = - 17/3 = - 5 2/3 Ответ ( - 5 2/3 )