Hai sir,,, what is the variable line and variable circle?

A Variable line may be a general line which gives different equations depending upon the different variables. Example – ax + by + c = 0 is a variable or general line, which can be uniquiely definied for a fixed set of valus of a, b and c. We may also be given the values of few variables but not all for a variable line. Example – 2x + 4y + c = 0 is also a variable line.

Similarly, variable circle is a circle, which can have different equations depending upong the values of variables.

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