Question

find the equation of the circle with centre (1,2) radius 5

Answer 1

Answer:

Step-by-step explanation:

as compared with√(x-h)^2+(y-k)^2=r

given h=1 and k=2 r=5

squaring on both sides

(x-1)^2+(y-2)^2=25

x^2+1-2x+y^2+4-4y=25

x^2+y^2-2x-4y=20