# A 30-60-90 trangle with extension line for half angle identity

```						var board = JXG.JSXGraph.initBoard('box1', {
boundingbox: [-10, 10, 10, -10],showNavigation:false, showcopyright: false, axis: false,
});

var p1 = board.create('point', [-8, 3.62],{face:'',fixed:true});
var p2 = board.create('point', [-8, -1.0],{face:'',fixed:true});
var p3 = board.create('point', [0, -1.0],{face:'',fixed:true});
var l1 = board.create('segment', [p1, p2],{withLabel:true,name:'1/2',label:{offset:[-20,-5]}});
var l2 = board.create('segment', [p2, p3]);
var l3 = board.create('segment', [p3, p1],{withLabel:true,name:'1',label:{offset:[ 10,5]}});
var a1 = board.create('angle', [p1, p3, p2],{name:'30°', radius:1.5,label:{offset:[-8,-2]}});
var a2 = board.create('angle', [p2, p1, p3],{name:'60°', radius:1.5,label:{offset:[-5,-2]}});
p4 = board.create('point', [9.24, -1.0],{face:'',fixed:true,label:{offset:[-10,15]}});
var l4 = board.create('segment', [p3, p4],{dash:2});
var l5 = board.create('segment', [p1, p4],{dash:2});
var a3 = board.create('angle', [p1, p4, p3],{name:'15°', radius:3.5,label:{offset:[-5,-2]}});
//var tm1 = board.create('tapemeasure', [[p1.X(), p1.Y()], [p3.X(), p3.Y()]], {name:'dist'});
//var tm1 = board.create('tapemeasure', [[p1.X(), p1.Y()], [p2.X(), p2.Y()]], {name:'dist'});

```
Scroll to Top