We use the letter n to represent the number of cards that You had yesterday.
Then, when you gave six cards away, the number of cards you have decreased by 6, i.e., now you have minus 6 cards than you had yesterday.
For example, if you had 10 cards and gave 6 away, the number of baseball cards you would have left would be:
[tex]10-6[/tex]
Instead of 10, in this problem, we need to write "n". Therefore, the expression we are looking for is:
[tex]\mathbf{n-6}[/tex]
