Areas of two circles are equal. Is it necessary that their circumferences are equal? Why?

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(A) Yes,it is necessary that their circumferences are equal.
Let the radii of the two circles be $r_1$ and $r_2$ respectively.
The area of a circle is given by the formula $A = \pi r^2$.
Given that the areas are equal,we have $\pi r_1^2 = \pi r_2^2$.
Dividing both sides by $\pi$,we get $r_1^2 = r_2^2$,which implies $r_1 = r_2$ (since radius must be positive).
The circumference of a circle is given by $C = 2\pi r$.
Since $r_1 = r_2$,it follows that $2\pi r_1 = 2\pi r_2$.
Therefore,the circumferences of the two circles must be equal.

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