Question

How do you find the center and radius for `x^2 + y^2 = 36`?

Answer 1

centre = (0 ,0), radius = 6

Explanation:

The standard form of the equation of a circle is.

`color(red)(|bar(ul(color(white)(a/a)color(black)((x-a)^2+(y-b)^2=r^2)color(white)(a/a)|))`
where (a ,b) are the coordinates of the centre and r, the radius.

The equation here can be expressed in this form, that is

`(x-0)^2+(y-0)^2=6^2`

By comparison with the standard equation.

centre = (0 ,0) and radius = 6