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General Form To Standard Calculator

Circle Equation Conversion:

\[ (x - h)^2 + (y - k)^2 = r^2 \]

from

\[ x^2 + y^2 + Dx + Ey + F = 0 \]

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From: To:

1. What is the General to Standard Form Conversion?

The calculator converts the general form of a circle equation (x² + y² + Dx + Ey + F = 0) to the standard form ((x - h)² + (y - k)² = r²), which clearly shows the center (h,k) and radius r of the circle.

2. How Does the Calculator Work?

The calculator uses the following conversion formulas:

\[ h = -\frac{D}{2} \] \[ k = -\frac{E}{2} \] \[ r = \sqrt{h^2 + k^2 - F} \]

Where:

Explanation: The conversion is done by completing the square for both x and y terms in the general form equation.

3. Importance of Standard Form

Details: The standard form makes it immediately obvious where the circle is centered and what its radius is, which is essential for graphing and geometric analysis.

4. Using the Calculator

Tips: Enter the D, E, and F coefficients from your general form equation. The calculator will determine if the equation represents a valid circle (r² > 0).

5. Frequently Asked Questions (FAQ)

Q1: What if I get "Invalid circle equation"?
A: This means the radius would be imaginary (r² ≤ 0), indicating your equation doesn't represent a real circle.

Q2: Can this calculator handle fractions?
A: Yes, you can enter decimal equivalents of fractions (e.g., 0.5 for 1/2).

Q3: What's the difference between general and standard form?
A: General form shows all terms expanded, while standard form clearly displays the geometric properties of the circle.

Q4: How do I know if my general form represents a circle?
A: After conversion, if r² > 0, it's a valid circle. If r² = 0, it's a single point, and if r² < 0, it's not a real circle.

Q5: Can I convert back from standard to general form?
A: Yes, by expanding the squared terms in the standard form equation.

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