Answer:
(x-18)^2+(y+6)^=36
Step-by-step explanation:
circle basic equation is (x-h)^2+(y-k)^2=r^2
center is (18,-6) it is also externally tangent
so
(x-18)^2+(y+6)^2=36 answer
12f + 49g
12f -7g(-7)