Answer:
If you're looking for a shortcut, I usually find the number 1 less than what you are multiplying 9 by, this case 8, and then add a number that gets to 9.
So 9x6 would be:
5+4=9
54
Explanation:
When multiplying by 9s the product's two numbers added together =9.
Sorry if this is confusing. Hope this helps though.