Is 4x + 53 = y a function or not a function?

If f(x)=2x^6+x^2+2 then what is the remainder when f(x)is divided by x+2

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.

Hardest math question of all time can you solve the equation. check for extraneous solutions.9∣9-8x∣ = 2x+3