Question

A circle is centered at (2, -5) and has radius 3. How do you write its equation in standard form?

Answer 1

`(x - 2 )^2 + ( y + 5 )^2 = 9`

Explanation:

The standard form of the equation of a circle is :

`(x - a )^2 + (y - b )^2 = r^2`

where (a , b ) are the coordinates of the centre and r = radius .

in this question (a , b ) = (2 , -5 ) and r =3

( substituting these values into the standard form equation )

`rArr (x - 2 )^2 + (y + 5 )^2 = 9`