what is the equation of the circle with center (0, 0) that passes through the point (-5, -5)?

Question

hartnn · Answer

Equation of circle passing through centre is of the form 
$\huge x^2+y^2=r^2$

now just plug in x= -5
y=-5
and find r :)

anonymous · Answer

I know how to do it but I don't know if my answer is right =/

hartnn · Answer

what answer you got ?

anonymous · Answer

x2  + y2 = 50

hartnn · Answer

thats absolutely correct! :)

anonymous · Answer

thank you! can you help me with  few more?

hartnn · Answer

sure :)

haseeb96 · Answer

good job @hartnn

haseeb96 · Answer

and @Jessica_sunshinexx  u too...

anonymous · Answer

what are the center and radius of the circle with equation (x-1)^2 + (y+4)^2 =4?

hartnn · Answer

the standard equation is 
$\huge (x-h)^2 +(y-k)^2 =r^2$

where, (h,k) is the center of the circle
and r= radius of circle

hartnn · Answer

you just need to compare the equation in the question to find the values of h,k and r^2

hartnn · Answer

did u get what to do ?

anonymous · Answer

center 1 , -4   r + 2 is that the answer?   @hartnn

hartnn · Answer

absolutely correct! :)