ajax return

//HERE IS THE GETGEOY.PHP (getgeoX is just the same...

<?php

    include '../functions.php';
    session_start();
    if(isset($_POST['id'])){

        $db = connectToDb('julos');
        $db->setAttribute(\PDO::ATTR_ERRMODE, \PDO::ERRMODE_EXCEPTION);
        $db->setAttribute(\PDO::ATTR_EMULATE_PREPARES, false);
        $id = $_POST['id'];
        $getGeo = $db->prepare("SELECT Y(geo_position) AS y FROM geo WHERE geo_id = :id");
        $getGeo->execute(['id'=>$id]);
        if (!$getGeo->rowCount()) {
            echo ("false");
        }

        $y = $getGeo->fetchColumn(0);
        $getGeo->closeCursor();

        echo json_encode($y);
    }else{
        echo "ERREUR ID NOT SET";
    }

?>

//////////////////////////////////////////////////////////////////////////////////////////////////

// here is the problematic JS

function getGeoX(id){
        return $.ajax({
            type : 'POST',
            url : './php/utils/getGeoX.php',
            data : {'id':id},
            dataType : 'json',
            error : function(response){
                console.log("ERROR GET X "+response.responseText);
            },
            success : function(response){
                console.log("SUCCESS GET X "+response);

//THIS DISPLAYS THE RIGHT DATA WHICH IS A NUMBER !!!

            }
        });
    }
function getGeoY(id){
        return $.ajax({
            type : 'POST',
            url : './php/utils/getGeoY.php',
            data : {'id':id},
            dataType : 'json',
            error : function(response){
                console.log("ERROR GET Y "+response.responseText);
            },
            success : function(response){
                console.log("SUCCESS GET Y "+response);

//THIS DISPLAYS THE RIGHT DATA WHICH IS A NUMBER !!!

            }
        });
    }

//THE PROBLEM IS IN THE NEXT PART :

$("body").on("click",".gmLocate",function(){
        $("#idGeo").val(this.id);
        var lat = (getGeoX(this.id));
        var lng = (getGeoY(this.id));
        console.log("DISPLAY LAT : "+lat);

//THIS CONSOLE LOG DISPLAYS : DISPLAY LAT : [object Object]

        console.log("DISPLAY LNG : "+lng);

//THIS CONSOLE LOG DISPLAYS : DISPLAY LNG : [object Object]
//I have to get my value back... when i check what is in this object, i see this in the log :
//         readyState 4
//         responseJSON 50.244641280083
//         responseText "50.244641280083"
//         status 200
//         statusText "OK"
// ...
        .......................................
        .......................................
        .......................................