Function areaRectangle

Maths/Area.js:40–44

(length, width)

 * @example areaRectangle(4) = 16
 */
const areaRectangle = (length, width) => {
  validateNumericParam(length, 'Length')
  validateNumericParam(width, 'Width')
  return width * length
}

/**
 * @function areaSquare