randRangeNonZero( -2, 2 ) randRangeNonZero( -5, 5 ) randRangeNonZero( -5, 5 )

Adjust the focus coordinates and the equation of the directrix to make the blue parabola match the orange parabola.

All points on the blue parabola are equidistant from the focus and the directrix. How does changing the numbers affect the shape of the parabola?

graphInit({ range: 10, scale: 20, tickStep: 1, axisArrows: "<->" }); // Plot the orange parabola style({ stroke: "#FFA500", fill: "none", clipRect:[ [-10, -10], [20, 20] ], arrows: null }); plot( new Parabola( A, X1, Y1 ).graphieFunction, [-10, 10]); style({ stroke: "#6495ED", strokeWidth: 3, fill: "none", clipRect:[ [-10, -10], [20, 20] ], arrows: null }); graph.currParabola = new Parabola( 1, 0, 0 ); graph.currParabola.plot( true );

focus x coordinate: 0

focus y coordinate: 0.25

directrix: y=-0.25

[A, X1, Y1]
var parab = graph.currParabola; return parab.getLeadingCoefficient() === A && parab.getVertexX() === X1 && parab.getVertexY() === Y1;
guess = guess.length ? guess : [1, 0, 0]; var parab = graph.currParabola; parab.update.apply(parab, guess); redrawParabola(true);
guess = guess.length ? guess : [1, 0, 0]; // Update the graph parabola so we can use its methods // to get focus and directrix var parab = graph.currParabola; parab.update.apply(parab, guess); var fX = parab.getFocusX(), fY = parab.getFocusY(), dK = parab.getDirectrixK(); $("#focus-x-label").html("<code>" + fX + "</code>").tmpl(); $("#focus-y-label").html("<code>" + fY + "</code>").tmpl(); $("#directrix-label").html("<code>" + dK + "</code>").tmpl();