The polynomial −16t^2+550 gives the height of a ball t seconds after it is dropped from a 550-foot-tall building. Find the height after t=2 seconds.

Two times a number plus three times another number equals 4. three times the first number plus four times the other number is 7. find the numbers

In a singing competition, there are 150 participants. at the end of each round, 40% of the participants are eliminated. how many participants are left after n rounds?

The table below shows the number of free throw shots attempted and the number of shots made for the five starting players on the basketball team during practice. each player's goal is to make 80% of her shots.