To complete the square for the equation of the circle \(x^2 + y^2 - 10x + 4y = -13\), we start by rearranging it:
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Rearrange the equation: \[ x^2 - 10x + y^2 + 4y = -13 \]
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Complete the square for the \(x\) terms:
- Take the coefficient of \(x\), which is \(-10\), halve it to get \(-5\), and square it to get \(25\).
- Add and subtract \(25\) to the equation.
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Complete the square for the \(y\) terms:
- Take the coefficient of \(y\), which is \(4\), halve it to get \(2\), and square it to get \(4\).
- Add and subtract \(4\) to the equation.
Now, the equation becomes: \[ (x^2 - 10x + 25) + (y^2 + 4y + 4) = -13 + 25 + 4 \]
This simplifies to: \[ (x - 5)^2 + (y + 2)^2 = 16 \]
Now, we can identify the center and the radius:
- The center of the circle is \((5, -2)\).
- The radius is \(\sqrt{16} = 4\).
Thus, the answers are:
- Center: \(5, -2\)
- Radius: \(4\)
So, the final answer is: Center: 5, -2; Radius: 4