How do you graph #x^2+y^2-4x-2y-4=0#?
It is an equation of a circle with center in
From this form you can find out that the equation represents a circle.
To find its coordinates and radius you should transform it to form of:
We start from the equation given:
Now we can group terms with the same variable:
Now we can complete the squares of variables:
Now we can write the expressions with
Finally I can move
From this equation I can read that the equation shows a circle with center in