Решите систему уравнений 2(x + y)^2 7(x + y) + 3 = 0 2x 3y = -1

Ответы:

2*(x+y)^2-7(x+y)+3=0

(x+y)(2x+2y-7)+3=0

2x-3y=-1

2x=3y-1

x=(3y-1)/2

((3y-1)/2+y)*(3y-1+2y-7)+3=0

((3y-1+2y)/2)*(5y-8)+3=0  |*2

(5y-1)*(5y-8)+6=0

25y^2-40y-5y+8+6=0

25y^2-45y+14=0

d=25^2

y1=(45+25)/50=70/50=7/5

y2=(45-25)/50=20/50=2/5

x1=(3*7/5-1)/2

x2=(3*2/5-1)/2