<span>A. 8,648,640
B. 13
C. 665,280
D. 4,324,320
</span>Assume you don't watch movies twice.
If you have 13 movies to pick from, then you have 13 choices for the first movie. Then, only 12 choices are left. Do this until only 6 are left (13-7=6)
This equates to

Therefore, the answer is A, 8,648,640 different ways.
Hope this helps!
Add 5
5,10,15,20,25,30....
These two problems are equivalent
Where are the quadratic equations?
Let's factorise it :

![\: {\qquad \dashrightarrow \sf {x}^{3} (x + 3) + [-5(x + 3)] }](https://tex.z-dn.net/?f=%5C%3A%20%7B%5Cqquad%20%20%5Cdashrightarrow%20%5Csf%20%20%20%20%7Bx%7D%5E%7B3%7D%20%28x%20%2B%203%29%20%2B%20%5B-5%28x%20%2B%203%29%5D%20%20%7D)
Using Distributive property we get :



⠀
Therefore,
