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Задача Задача №2565307
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Аноним
23 декабря 2024 06:35 · публичный вопрос
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Аноним

x-y=3 xy=-20

Ответ нейросети
23 декабря 2024 06:35

To solve the system of equations

  1. \( x - y = 3 \) (Equation 1)
  2. \( xy = -20 \) (Equation 2)

we can start by expressing one variable in terms of the other using Equation 1.

From Equation 1, we can express \( x \) in terms of \( y \):

\[ x = y + 3 \]

Next, we can substitute this expression for \( x \) into Equation 2:

\[ (y + 3)y = -20 \]

Expanding this, we get:

\[ y^2 + 3y + 20 = 0 \]

Now, we can rearrange it into standard quadratic form:

\[ y^2 + 3y + 20 = 0 \]

Next, we will use the quadratic formula to find the roots of this equation, where \( a = 1 \), \( b = 3 \), and \( c = 20 \):

\[ y = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \]

Calculating the discriminant:

\[ b^2 - 4ac = 3^2 - 4 \cdot 1 \cdot 20 = 9 - 80 = -71 \]

Since the discriminant is negative, there are no real solutions for \( y \), and consequently, no real solutions for \( x \).

Therefore, the system of equations has no real solution. The solutions would be complex. If you need, I can help find the complex solutions as well. Would you like to proceed with that?