I've been given 3 coordinates: (0,0), (2,0) and (0,2) and I'm asked to draw the circle and then determine the equation of the circle: .
Now, since r=2 and the center point is (0,0), I'd say the equation would be:
, my book tells me it should be (or something like that, don't have it with me). Could someone elaborate on this? I don't get where the -2x,-2y come from!
Took a while for me to get home (and to my book). The three coordinates given are indeed (0, 0), (2, 0) and (0, 2). And indeed you were right, none of these points is supposed to be the center. But that makes me wonder, how can i possibly draw a circle on which all these points lie?
Every triangle has a circle that passes through all its three vertices. As said in post #4, the circle in question has center (1, 1) and radius . In fact, when the triangle has a right angle, the circumcircle's center is the middle of the hypotenuse.