{x+y+xy=-1 {y^2+x^2-xy=7

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To solve this system of equations, we can start by solving the first equation for y in terms of x:

From the first equation, we have:
x + y + xy = -1
y + xy = -1 - x
y(1 + x) = -1 - x
y = (-1 - x)/(1 + x)

Now, we can substitute this expression for y into the second equation to solve for x:

(y^2) + x^2 - xy = 7
[(-1 - x)/(1 + x)]^2 + x^2 - x(-1 - x)/(1 + x) = 7
(x^2 + 2x + 1)/(1 + x)^2 + x^2 + x^2 + x = 7
x^2 + 2x + 1 + (1 + 2x + x^2)(1 + x)^2 = 7(1 + x)^2
x^2 + 2x + 1 + (1 + x)^2(1 + 2x + x^2) = 7(1 + x)^2
x^2 + 2x + 1 + (1 + 2x + x^2 + 2x + 4x^2 + 2x^3) = 7(1 + x)^2
x^2 + 2x + 1 + 1 + 2x + x^2 + 2x + 4x^2 + 2x^3 = 7(1 + 2x + x^2)
2x^3 + 6x^2 + 6x + 2 = 7(1 + 2x + x^2)
2x^3 + 6x^2 + 6x + 2 = 7 + 14x + 7x^2
2x^3 + 6x^2 + 6x + 2 = 7 + 14x + 7x^2
2x^3 - x^2 + 8x - 5 = 0

The solutions to this cubic equation may be complex, and it may not be possible to find explicit values for x and y algebraically. Additional numerical methods or graphical approaches may be needed to find approximate solutions.