# A circle has the equation x^2+y^2=16. How do you find the center ,radius and the intercepts?

Mar 5, 2016

centre (0,0) , r=4 , (±4,0), (0,±4)

#### Explanation:

The standard form of the equation of a circle is

${\left(x - a\right)}^{2} + {\left(y - b\right)}^{2} = {r}^{2}$

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

${x}^{2} + {y}^{2} = 16 \text{ is in this form }$

with a = b = 0 and r = 4

hence this circle has centre at the origin (0,0) and radius 4

The intercepts will therefore be (± 4,0) and (0, ± 4 )