Tham khảo câu trả lời từ Trợ lý ảo Lazi To solve the equation \( xy + x + y + 2 = 0 \), we can first rearrange it: \[ xy + x + y = -2 \] Next, let's aim to factor or to rewrite this equation. One helpful approach is to recognize that we can rearrange this equation in a way to see if it can be factored. We can group \( x \) and \( y \) terms: \[ xy + x + y + 1 = -1 \] Now, we can rewrite this as: \[ (x + 1)(y + 1) = -1 \] Thus: \[ (x + 1)(y + 1) = -1 \] Now we can analyze this equation. The product of the two factors \( (x + 1) \) and \( (y + 1) \) must equal -1. This means that we can express \( y + 1 \) in terms of \( x + 1 \): \[ y + 1 = \frac{-1}{x + 1} \] Subtracting 1 from both sides yields: \[ y = \frac{-1}{x + 1} - 1 = \frac{-1 - (x + 1)}{x + 1} = \frac{-x - 2}{x + 1} \] So, we have: \[ y = \frac{-x - 2}{x + 1} \] Now we can find the values of \( x \) and \( y \) that satisfy the original equation by choosing specific values of \( x \) or \( y \). For example: - If \( x = 0 \): \[ y = \frac{-0 - 2}{0 + 1} = -2 \] So, one solution is \( (0, -2) \). - If \( y = 0 \): \[ x = \frac{-0 - 2}{0 + 1} = -2 \] So, another solution is \( (-2, 0) \). These points \( (0, -2) \) and \( (-2, 0) \) are examples of solutions, but the equation represents a hyperbola, so there are infinitely many solutions. Group the solutions as \( (x, y) \) pairs based on the derived relationship. In conclusion, the set of solutions to the equation \( xy + x + y + 2 = 0 \) can be described by the relationship: \[ y = \frac{-x - 2}{x + 1} \] for \( x \neq -1 \) (since that would lead to division by zero).