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Solve the following system of equations:
xy = -4
2y = x- 6
Answer choices:
A. (-1, 4), (-2, 2)
B. (2,-2), (4, -1)
C. (4,3), (-3,-4)
D. (-4, 12).(-1, -3)

Respuesta :

nktselepov

[tex]xy = 4 \\ 2y = x - 6 \\ \\ xy = 4 \\ x = 6 + 2y[/tex]

[tex](6 + 2y)y = - 4 \\ {y}^{2} + 3y + 2 = 0 \\ d = {3}^{2} - 4 \times 2 = 9 - 8 = 1 = {1}^{2} [/tex]

[tex]y = \dfrac{ - 3 + 1}{2} = - 1 \\ \\ y = \dfrac{ - 3 - 1}{2} = - 2[/tex]

[tex] - 2x = - 4 \\ x = 2 \\ \\ - x = - 4 \\ x = 4[/tex]

Answer: B) (2; -2), (4; -1)

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