Question

Coloque na forma (x-a)² + (y-b)²= r²
a) x²+y²-2x=0

Answer 1

$x^2+y^2-2x=0\\ \\ x^2-2x+1+y^2=1\\ \\ (x-1)^2+(y-0)^2=1\\ \\ a=1\\ b=0\\ r^2=1$