X=2y-3
3(2y-3)+y=1
6y-9+y=1
x=2y-3
7y=10
x=2y-3
y=10/7
x=2*10/7-3
x=20/7-3=2 6/7-3=-1/7
y=1 3/7
D = 4 + 20 = 24
√ D = √ 24 = 2 √ 6
X1 = ( 2 + 2 √ 6 ) : 2 = 1 + √ 6
X2 = ( 2 - 2 √ 6 ) : 2 = 1 - √ 6
X1 * X2 = ( 1 + √ 6 )*( 1 - √ 6 ) = 1 - 6 = - 5
ОТВЕТ МИНУС 5