Write an equation for a circle centered at 16 with radius 4S

Write an equation for a circle centered at (1,-6) with radius 4.

Solution

equation of circle with centre (h,k) radius r is (x-h)²+(y-k)²=r²

equation of circle with centre (1,-6) radius 4 is (x-1)²+(y-(-6))²=4²

(x-1)²+(y+6)²=16

x²-2x +1 +y²+12y +36 =16

x² -2x +y² +12y +21 =0