( х^2 - 9 )^2 + 32( х^2 - 9 ) - 273 = 0
Х^2 - 9 = а
а^2 + 32а - 273 = 0
D = 1024 + 1092 = 2116 = 46^2
a1 = ( - 32 + 46 ) : 2 = 7
a2 = ( - 32 - 46 ) : 2 = - 39
X^2 - 9 = 7
X^2 = 16
X = ( + ; - ) 4
X^2 - 9 = - 39
X^2 = - 30 ( нет решений )
4 * ( - 4 ) = - 16
Ответ ( - 16 )