@@ -0,0 +1,29 @@
+'use strict';
+
+class Rectangle {
+constructor(height, width) {
+this.height = height;
+this.width = width;
+}
+
+get area() {
+return this.height * this.width;
+}
+}
+
+class Square extends Rectangle {
+constructor(side) {
+super(side, side);
+}
+
+get side() {
+return this.height;
+}
+}
+
+// Usage
+
+const square = new Square(100);
+console.dir({ square });
+console.log('square.area:', square.area);
+console.log('square.side:', square.side);