JSFiddle - React, Tailwind, and code Playground
JavaScript
var beaconCoordinates = [[10,20], [200,300], [50,500]];
//get values from array
var aX = parseInt(beaconCoordinates[0][0]);
var aY = parseInt(beaconCoordinates[0][1]);
var bX = parseInt(beaconCoordinates[1][0]);
var bY = parseInt(beaconCoordinates[1][1]);
var cX = parseInt(beaconCoordinates[2][0]);
var cY = parseInt(beaconCoordinates[2][1]);
console.log(cY);