Answer:

Step-by-step explanation:
Answer:
y = 3x + 4
Step-by-step explanation:
According to the given question, the expression to represent all the books in Ms. Canton's bookcase is shown below:-
y indicates the total amount of books
x indicates the equal cost of books on 3 bookshelves
while
+4 indicates 4 other books on the fourth bookshelf
So, the expression will be
y = 3x + 4
Therefore the correct answer is y = 3x + 4
ANSWER: The number is 10.
Hope this helps!!
I used the variable n as the number we needed to find. The equation was n + 8 + 12 = 3n