# How do you find the radius and center of a circle with the equation #( x - 1) ^2 + (y - 3) ^2 =16#?

##### 1 Answer

Mar 13, 2016

radius = 4 , centre = (1,3)

#### 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 centre and r , the radius

the equation

#(x - 1 )^2 + (y - 3 )^2 = 16 " is in this form "# and by comparison , centre = (1 , 3) and r = 4