



 
Tom, The equation of Area of an Ellipse is A = π a b where a and b are half the lengths of the major and minor axis. If we think of a circle, it is just a special case of an ellipse where a = b, the radius of the circle. That is why we say A = π a^{2} Looking at the formula, we can say that a is half the length and b is half the width. We just have to now manipulate the formula to find 2a in terms of A and 2b. Karen and Sue  


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