Question

{x²+y²=25{x-y=7
Решить систему уравнений

Answer 1

Х^2 + y^2 = 25
X - y = 7
X = y + 7
( y + 7 )^2 + y^2 = 25
y^2 + 14y + 49 + y^2 = 25
2y^2 + 14y + 24 = 0
D = 196 - 192 = 4 = 2^2
y1 = ( - 14 + 2 ) : 4 = - 3
y2 = ( - 14 - 2 ) : 4 = - 4
X1 = - 3 + 7 = 4
X2 = - 4 + 7 = 3
Ответ ( 4 ; - 3 ) ; ( 3 ; - 4 )