One way would be to find the distance from the point to the center of the circle and compare it to the radius
for
the center is (h,k) and the radius is r
and the distance formula is
distance between
and 
is
r=radius
D=distance form (8,4) to center
if r>D, then (8,4) is inside the circle
if r=D, then (8,4) is on the circle
if r<D, then (8,4) is outside the circle
so
the radius is
center is (-2,3)
find distance between (8,4) and (-2,3)
≈4.2
≈10.04
do r<D
(8,4) is outside the circle
for
the center is (h,k) and the radius is r
and the distance formula is
distance between
r=radius
D=distance form (8,4) to center
if r>D, then (8,4) is inside the circle
if r=D, then (8,4) is on the circle
if r<D, then (8,4) is outside the circle
so
the radius is
center is (-2,3)
find distance between (8,4) and (-2,3)
do r<D
(8,4) is outside the circle