Identify a pattern in the given list of numbers 87,71,55,39,23 what is the next number

Y=4x^2+x-1 solve using quadratic formula

Josh has a rewards card for a movie theater he receives 15 points for becoming a rewards card holder he earns 3.5 points for each visit to the movie theater he needs at least 55 points to earn a free movie ticket which inequality can josh use to determine x, the minimum number of visits he needs to earn his first free movie ticket.

The value of cos 30° is the same as which of the following?