How do you find the center and radius of (x+2)^2+(y+4)^2=256?

1 Answer
Apr 18, 2016

centre=(-2 , -4) , r = 16

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 coords of centre and r , the radius.

(x + 2)^2 + (y + 4)^2 =256" is in this form "

and by comparison: a = -2 , b = -4 and r = sqrt256 =16

hence : centre = (-2 ,-4) and radius = 16