What is the equation of a circle with center (6,4) that passes through the coordinate (2,1)?

Question

mathmale · Answer

Would you look up and type out here the general equation of a circle with center at (h,k) and radius r, please?  Then we'll get to work on your math problem.

anonymous · Answer

circle: (x - h)2 + (y - k)2 = r2
radius: is the r2 in that equation.

mathmale · Answer

OK.  Good.  You are told that the center of your circle is (6,4).
Modify your equation accordingly.  Type out the result here, please.

anonymous · Answer

Im confused

anonymous · Answer

I don't know how to set up the equation.

mathmale · Answer

You were correct in typing out (x - h)2 + (y - k)2 = r2, which in more formal notation is$$(x - h)^2 + (y - k)^2 = r^2$$   You told me that the center of your particular circle is (6,4).  That means your h=6 and your k=4.

I'm asking you to substitute those values of h and k into your $(x - h)^2 + (y - k)^2 = r^2$ now.

anonymous · Answer

i figured it out. the 6,4 is the k,h so i plugged it in and the other coordinates are x,y i plugged them in.