Question

Is a circle an ellipse?

Answer 1

Checking if a circle is an ellipse

An ellipse is a locus of points in a plane, the sum of whose distance from two fixed points is a constant value.

Considering a circle, we know that the circle has the same radius for all the points on the circumference. So, the circle is also a locus of points in a plane whose sum of distance from two fixed points is a constant value.

Therefore, we can say that circle is a special kind of ellipse. When a circle is stretched in the $x$ or $y$ direction, an ellipse is formed.

Hence, a circle is also an ellipse.