Question

Which of the following is a degenerate circle?
answer choices A,B,C,D from top to bottom

Answer 1

Hello,

we may call a point as a degenerated circle :
(x-5)²+(y-1)²=0 is the point (5;1)

Answer A

Answer 2

A.
`(x-5)^2+(y-1)^2=0`

Explanation:

When the radius of a circle is zero, then it is called a degenerate circle.

The general equation of circle with center at
`(h,k)` and radius of r is,

`(x-h)^2+(y-k)^2=r^2`

So the radius is 0, so the equation will be in form of,

`(x-h)^2+(y-k)^2=0`

Out of the given option A has is a circle with radius of 0.

`(x-5)^2+(y-1)^2=0^2`