..........................
X^2 - 4X + 4 + 24 = 4 + 12X + 9X^2
9X^2 - X^2 + 12X + 4X + 4 - 28 = 0
8X^2 + 16X - 24 = 0
D = 256 + 768 = 1024
V D = 32
X1 = ( - 16 + 32 ) : 16 = 1
X2 = ( - 3 )
-------------------------
( X1 + X2 ) * ( - 6)
( 1 - 3 ) * ( - 6) = ( - 2 ) * ( - 6) = 12
--------------
Ответ 12 ( под цифрой 3 )