Question

Which equation represents a circle with a center at (2, –8) and a radius of 11?

Answer 1

The equation of a circle is defined by:  (x - h)² + (y - k)² = r²  where
(h,k) represents the center of your circle and r = the radius

So (x - 2)² + (y + 8)² = 121 is your equation

Answer 2

Answer:

The  equation of circle is $x^2+y^2-4x+16y-61=0$        

Step-by-step explanation:

Given : A circle with a center at (2, –8) and a radius of 11.

To find : Which equation represents a circle?

Solution :

The general equation of the circle is

$(x-h)^2+(y-k)^2=r^2$

Where, (h,k)=(2,-8) is the center and r is the radius r=11.

Substitute the value in the formula,

$(x-2)^2+(y-(-8))^2=11^2$

$x^2-4x+4+y^2+16y+64=121$

$x^2+y^2-4x+16y+60=121$

$x^2+y^2-4x+16y-61=0$

Therefore, The  equation of circle is $x^2+y^2-4x+16y-61=0$