# A 5-circle incidence theorem

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Revision as of 14:30, 13 August 2019 by A WASSERMANN (talk | contribs)

This is a visualization of *A 5-Circle Incidence Theorem* by J. Chris Fisher, Larry Hoehn and Eberhard. M. Schröder,
Mathematics Magazine, Volume 87, 2014 - Issue 1.

### The underlying JavaScript code

```
var board = JXG.JSXGraph.initBoard('jxgbox',{boundingbox:[-5,5,5,-5]});
var A = [], s = [], B = [], c = [], r = [], k;
var attA = {name:'',strokeColor: '#7355ff', fillColor: '#7355ff'};
A[0] = board.create('point', [2.5, -3], attA);
A[1] = board.create('point', [2, 4], attA);
A[2] = board.create('point', [-2.5, 3], attA);
A[3] = board.create('point', [-4, -2], attA);
A[4] = board.create('point', [0, -4], attA);
for (k = 0; k < 5; k++) {
s[k] = board.create('segment',[A[k], A[(k + 2) % 5]],{strokeColor:'blue',strokeWidth:1});
}
var attB = {name: '', strokeColor: '#EA0000', fillColor: '#EA0000'};
for (k = 0; k < 5; k++) {
B[k] = board.create('intersection', [s[k], s[(k-1+5)%5], 0], attB);
}
var attC = {strokeColor: '#aaaaaa', strokeWidth: 1};
for (k = 0; k < 5; k++) {
c[k] = board.create('circle', [A[k], B[k], A[(k+1)%5]], attC);
}
var attR = {strokeColor: '#ff0000', strokeWidth: 2};
for (k = 0; k < 5; k++) {
r[k] = board.create('radicalaxis', [c[k], c[(k-1+5)%5]], attR);
}
```