Use the factor theorem to determine which expression is a factor of the following polynomial

What is the value of r of the geometric series?

Using only the digits 5, 6, 7, 8, how many different three digit numbers can be formed if no digit is repeated in a number?

Officer brimberry wrote 32 tickets for traffic violations last week, but only 4 tickets this week. what is the percent decrease? give your answer to the nearest tenth of a percent.