Consider the following system of equations:

{
−x+y=5
y=(x−3)
2
+2

1 answer

To solve the system of equations:

  1. \(-x + y = 5\)
  2. \(y = \frac{(x - 3)^2}{2} + 2\)

We can first express \(y\) from the first equation:

From equation 1: \[ y = x + 5 \]

Now, we can substitute \(y\) into equation 2:

\[ x + 5 = \frac{(x - 3)^2}{2} + 2 \]

Now, let's simplify and solve this equation:

  1. Multiply both sides by 2 to eliminate the fraction: \[ 2(x + 5) = (x - 3)^2 + 4 \]

  2. Distribute on the left side: \[ 2x + 10 = (x - 3)^2 + 4 \]

  3. Expand the right side: \[ 2x + 10 = x^2 - 6x + 9 + 4 \]

  4. Combine like terms on the right: \[ 2x + 10 = x^2 - 6x + 13 \]

  5. Rearrange the equation to one side: \[ 0 = x^2 - 6x - 2x + 13 - 10 \] \[ 0 = x^2 - 8x + 3 \]

Now we have a quadratic equation: \[ x^2 - 8x + 3 = 0 \]

We can solve this using the quadratic formula: \[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] where \(a = 1\), \(b = -8\), and \(c = 3\).

Calculating the discriminant: \[ b^2 - 4ac = (-8)^2 - 4(1)(3) = 64 - 12 = 52 \]

Now applying the quadratic formula: \[ x = \frac{-(-8) \pm \sqrt{52}}{2(1)} = \frac{8 \pm \sqrt{52}}{2} \]

\(\sqrt{52}\) can be simplified: \[ \sqrt{52} = \sqrt{4 \times 13} = 2\sqrt{13} \]

Thus, we have: \[ x = \frac{8 \pm 2\sqrt{13}}{2} = 4 \pm \sqrt{13} \]

This gives us two values for \(x\): \[ x_1 = 4 + \sqrt{13}, \quad x_2 = 4 - \sqrt{13} \]

Now, we can find corresponding \(y\) values for each \(x\):

Using \(y = x + 5\):

  1. For \(x_1 = 4 + \sqrt{13}\): \[ y_1 = (4 + \sqrt{13}) + 5 = 9 + \sqrt{13} \]

  2. For \(x_2 = 4 - \sqrt{13}\): \[ y_2 = (4 - \sqrt{13}) + 5 = 9 - \sqrt{13} \]

Thus, the solutions to the system of equations are: \[ (4 + \sqrt{13}, 9 + \sqrt{13}) \quad \text{and} \quad (4 - \sqrt{13}, 9 - \sqrt{13}) \]