Answer:
1) (x + 12)²+(y+6)²= 28
comparing above equation with(x-h)²+(y-k)²=r²
we get
r=√28
h=-12
k=-6
;.centre=(-12,-6)
radius =√28 units
2) x²+(y+7)²=15
comparing above equation with(x-h)²+(y-k)²=r²
we get
r=√15
h=0
k=-7
;.centre=(0,-7)
radius=√15 units
3) (x + 4)²+(y - 1)² = 4
comparing above equation with(x-h)²+(y-k)²=r²
we get
r=√4=2units
h=-4
k=1
;.centre=(-4,1)
radius=√2units
4) (x+3)²+(y-1)²= 8
comparing above equation with(x-h)²+(y-k)²=r²
we get
r=√8=2√2units
h=-3
k=1
;.centre=(-3,1)
radius=2√2units