5y - x = 4
X^2 + 3y^2 = 4
••••••
X = 5y - 4
( 5y - 4 )^2 + 3y^2 = 4
25y^2 - 40y + 16 + 3y^2 - 4 = 0
28y^2 - 40y + 12 = 0
4( 7y^2 - 10y + 3 ) = 0
D = 100 - 84 = 16 = 4^2
y1 = ( 10 + 4 ) : 14 = 1
y2 = ( 10 - 6 ) : 14 = 2/7
X = 5y - 4
X1 = 5•1 - 4 = 1
X2 = 5•( 2/7 ) - 4 = ( 10/7 ) - 4 = 1 3/7 - 3 7/7 = - 2 4/7
Ответ ( 1 ; 1 ) ; ( - 2 4/7 ; 2/7 )