SOLUTION: State the center and the radius of the circle represented by the equation (x – 8) 2 + (y + 2)2 = 81

Algebra ->  Linear-equations -> SOLUTION: State the center and the radius of the circle represented by the equation (x – 8) 2 + (y + 2)2 = 81       Log On


   

Question 363654: State the center and the radius of the circle represented by the equation
(x – 8) 2 + (y + 2)2 = 81
Found 2 solutions by Fombitz, ewatrrr:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Compare to the general equation for a circle centered at (h,k) with a radius R:
.
.
%28x-h%29%5E2%2B%28y-k%29%5E2=R%5E2
.
.
(h,k)=(8,-2)
R=9

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi, 

*Note: standard form of an equation of a circle with radius r and center at (a,b)

(x- a)^2 + (x - b)^2 = r^2



(x – 8)^2  + (y + 2)^2 = 81

center = (8,-2)

radius 9