You have 13 different books at home that you can read. You want to pick 2 to read and you don't care about what order you read them. How many different combinations can you read 2 books out of 12?

What is an alternate exterior angle

The serenity and the mystic are sail boats. the serenity and the mystic start at the same point and travel away from each other in opposite directions. the serenity travels at 16 mph and the mystic travels at 19 mph. how far apart will they be in 3 hours?

Factor the polynomial. b^2 + 4b + 4