Answer:
(1, -2)
Step-by-step explanation:
The equation of a circle:
[tex](x-h)^2+(y-k)^2=r^2[/tex]
(h, k) - center
r - radius
We have:
[tex]x^2-2x+y^2+4y=4\qquad\text{add}\ 1^2\ \text{and}\ 2^2\ \text{to both sides}\\\\x^2-2x+1^2+y^2-2(-2)(y)+2^2=2(1^2)(2^2)\qquad\text{use}\ (a\pm b)^2=a^2\pm2ab+b^2\\\\(x-1)^2+(y-(-2))^2=8\\\\h=1,\ k=-2\to(1,\ -2)[/tex]
