Standard Equation

The equation x²/a² + y²/b² = 1 represents an ellipse centered at the origin. The values of a and b determine the shape and size of the ellipse.

If a > b, the ellipse is horizontal, with vertices at (±a,0) and foci at (±c,0), where c² = a² - b².

If b > a, the ellipse is vertical, with vertices at (0,±b) and foci at (0,±c), where c² = b² - a².

    y = ± √(b² - b²(x²/a²))
    x = ± √(a² - a²(y²/b²))

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