Question

Identify the center and the radius of each. x^+y^+26x-22y+281=0

Answer 1

Answer:

Center (-13,11) , radius 3

Step-by-step explanation:

The given circle has equation

$x^2+y^2+26x-22y+281=0$

We compare this to the general equation.

$x^2+y^2+2ax+2by+c=0$

where (-a,-b) is the center.

This implies that;

2a=26

$\Rightarrow a=13$

2b=-22

b=-11

The center is therefore (-13,11)

The radius is given by

$r=\sqrt{a^2+b^2-c}$

$r=\sqrt{13^2+(-11)^2-281}$

$r=\sqrt{9}$

The radius is 3