Find the equation of a circle with centre ` (h, k)` and touching the x -axis.

Options

A. `x^(2)+y^(2)-2hx+h^(2)=0`
B. `x^(2)+y^(2)-2hx-2ky+h^(2)=0`
C. `x^(2)+y^(2)-2hx-2ky+h^(2)=0`
D. `x^(2)+y^(2)-2hx-2ky=0`

Answer

A

Explanation

Required equation is `(x-h)^(2)+(y-k)^(2)=k^(2)`
`rArr x^(2)+y^(2)-2hy-2ky+h^(2)=0`