Can someone help me find the slope

Identify a1 and r for the geometric sequence an= -256(-1/4) n-1

Hector and alex traded video games. alex gave hector one fourth of his video games in exchange for 6 video games. then he sold 3 video games and gave 2 video games to his brother. alex ended up with 16 video games. how many video games did alex have when he started?

Can somebody 1. what is the formula for finding the vertical distance between two points on a coordinate plane?