Question

The equation of the circle with centre $(0,2)$ and radius 2 is $x^2+y^2-my=0$. The value of $m$ is

• A. 1
• B. 2
• C. 4
• D. 3

Answer 1

Answer: (C)

Here $h=0,k=2$ and $r=2$. Therefore, the required equation of the circle is:
$(x-0{)}^2+(y-2{)}^2=(2{)}^2$
or $x^2+y^2-4y+4=4$ or $x^2+y^2-4y=0$