Is (2,1),(4,3),(6,5),(2,7) a function

Jenny earned a 77 on her most recent test jenny score is no less then 5 points greater then 4/5 of terrance’s score if t represents terrance score which inequality represents the situation

Find the ratios of the corresponding sides

Find the length of the normal and the angle it makes with the positive x-axis. (see pictured below)