Х^2 - 11y = 26
x - y = 4
Решение
y = x - 4
x^2 - 11( x - 4 ) = 26
x^2 - 11x + 44 - 26 = 0
x^2 - 11x + 18 = 0
D = 121 - 72 = 49 ; V D = 7
x1 = ( 11 + 7 ) : 2 = 9
x2 = ( 11 - 7 ) : 2 = 2
y = x - 4
y1 = 9 - 4 = 5
y2 = 2 - 4 = - 2
Ответ ( 9 ; 5 ) ; ( 2 ; - 2 )