How to calculate an angle?

Question

JavaScript

You need to find the angle from three points, point B is the end of the segment AB and the beginning of BC :

var Point = function(x, y) {
this.x = x;
this.y = y;
}
var getAngle = function(a, b, c) {
// do something
return angle;
}
var a = getAngle(new Point(7,2), new Point(4,5), new Point(7,11));

Answer 1

Needed for this: jsfiddle.net/jd32v88o

Answer 2

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Answer 3

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