Question

Решите систему уравнений { x - y = 2 и xy = 15

Answer 1

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Answer 2

X= 2+y;
(2+y)y+15;
2y + y^2 = 15
y^2+2y-15=0
D= 4+60=64
y1= -2+8/ 2=3
y2=-2-8/2=-5
x1= 2+3=5
x2= 2-5=-3