Question

HELP ME PLEASE !
1. x^2+y^2=64
c= r=
2. (x-1)^2+y^2=49\
c= r=
3. (x+3)^2+(y+9)^2=49
c= r=
4. x^2+y^2-4x-4y-6=0
c= r=

Answer 1

general form
(x-a)^2 + (y-b)^2 = r^2
c=(a,b)

Answer 2

1.c=(0,0) r=8
2.c=(1,0) r=7
3.c=(-3,-9) r=7
4.make general form
x^2-4x+4-4+y^2-4y+4-4-6=0
x^2-4x+4=(x-2)^2
y^2-4y+4=(y-2)^2
(x-2)^2 -4 +(y-2)^2 -4 -6=0
(x-2)^2+(y-2)^2-4-4-6=0
(x-2)^2+(y-2)^2=14
c=(2,2) r=14^(1/2)

Answer 3

thank you @gorv !