X - 4y = 3
X = 4y + 3
X^2 = 16y^2 + 24y + 9
16y^2 + 24y + 9 - 2y = 9
16y^2 + 22y = 0
2y( 8y + 11 ) = 0
2y = 0 ; y1 = 0
8y + 11 = 0 ; y2 = - 11/8 = - 1 3/8
x = 4y + 3
x1 = 3
x2 = 4•( - 11/8 ) + 3 = - 11/2 + 3 = - 5,5 + 3 = - 2,5
Ответ ( 3 ; 0 ) ; ( - 2,5 ; - 1 3/8 )