The a=b; is also valid but when the b has its own value but in here b is just a undefined. if you want the value of b to be 7. then try an approach where you do the same but the variable your assigning to has a value.
It is great that you solved the challenge, but instead of posting your full working solution, it is best to stay focused on answering the original poster’s question(s) and help guide them with hints and suggestions to solve their own issues with the challenge. How to Help Someone with Their Code Using the Socratic Method
We are trying to cut back on the number of spoiler solutions found on the forum and instead focus on helping other campers with their questions and definitely not posting full working solutions.