What is the factored form of the expression: 64x2−9 ?

There were 816 people at a concert when a band started to play. after each song, only half the people stayed to hear the next song. how many people were left at the concert after x songs? write a function to represent this scenario.

You are cycling around europe with friends. you book into a hostel and you ask the owner what the ratio of men to women is currently staying there. there are 24 men and 6 women. what is the ratio of men to women in its simplest form?

Ben is three times as old as samantha, who is two years older than half of michel's age. if michel is 12. how old is ben?