How To Define Area in Switch Case in JavaScript

let area = "circle";
let PI = 3.142,
  l = 9,
  b = 7,
  r = 6;
switch (area) {
  case "circle":
    console.log("Area of the circle is : " + PI * r ** 2);
    break;
  case "triangle":
    console.log("Area of the triangle is : " + (l * b) / 2);
    break;
  case "rectangle":
    break;
    console.log("Area of the rectangle is : " + l * b);
  default:
    console.log("please enter valid data");
}