JSFiddle - React, Tailwind, and code Playground

HTML

<div id="output"></div>

JavaScript

polygone=   [
    [43.163834,-84.134153],
    [43.163834,-83.420042],
    [42.790073,-82.975095],
    [42.519397,-82.876218],
    [42.206868,-83.112424],
    [42.076528,-83.200315],
    [42.117288,-83.524412],
    [42.239411,-84.079221],
    [42.652862,-84.227537],
    [42.914912,-84.255002],
    [43.127763,-84.145139],
    [43.161783,-84.134016]
]

function isPointInPoly(point, vs) {    
    var x = point[0], y = point[1];
    
    var inside = false;
    for (var i = 0, j = vs.length - 1; i < vs.length; j = i++) {
        var xi = vs[i][0], yi = vs[i][1];
        var xj = vs[j][0], yj = vs[j][1];
        
        var intersect = ((yi > y) != (yj > y))
            && (x < (xj - xi) * (y - yi) / (yj - yi) + xi);
        if (intersect) inside = !inside;
    }
    
    return inside;
    
};
    
if (navigator.geolocation) {
  navigator.geolocation.getCurrentPosition(function(position) {
    const latitude = position.coords.latitude;
    const longitude = position.coords.longitude;
    console.log(`Latitude: ${latitude}, Longitude: ${longitude}`);
  });
} else {
  console.log("Geolocation is not supported by this browser.");
}


//if(isPointInPoly([ $latitude, $longitude ], polygone) === true) {
//    $("#output").html('Yup');
//} else {
//    $("#output").html('Nope');
//}


jQuery(window).ready(function () {
    $("#output").html(isPointInPoly([ 42.9948928, -83.689472 ], polygone));
});


console.log(isPointInPoly([42.9948928, -83.689472], polygone));