randRange(-5, 5) randRange(-5, 5) randRange(1, 5) H === 0 ? "x^2" : expr(["^", ["+", "x", -H], 2]) K === 0 ? "y^2" : expr(["^", ["+", "y", -K], 2])

Graph the circle ```expr(["+", X2T, Y2T]) = R * R```.

graphInit({ range: 11, scale: 20, axisArrows: "<->", tickStep: 1, labelStep: 1, gridOpacity: 0.05, axisOpacity: 0.2, tickOpacity: 0.4, labelOpacity: 0.5 }); label( [ 0, 11 ], "y", "above" ); label( [ 11, 0 ], "x", "right" ); addMouseLayer(); graph.circle = addCircleGraph();
Drag the center point and perimeter of the circle to graph the equation.
[ graph.circle.center[0], graph.circle.center[1], graph.circle.radius]
if (_.isEqual(guess, [0, 0, 2])) { return ""; } return _.isEqual(guess, [H, K, R]);
The equation of a circle with center `(\blue{h}, \green{k})` and radius `\pink{r}` is ```(x - \blue{h})^2 + (y - \green{k})^2 = \pink{r}^2```.
We can rewrite the given equation as ```(x - \blue{negParens(H)})^2 + (y - \green{negParens(K)})^2 = \pink{R}^2```.
Thus, the center of the circle should be ```(\blue{H}, \green{K}) ``` and the radius should be `\pink{R}`.