you take the two points that you have, plug them into y2-y1 and then x2-x1. that’s how you find your slope. then take whatever points you want that are given, and plug them into y=mx+b formula so for this it would be: 13= 3(5)+b and then solve for b. you should get this answer: y=3x-2 and i attached along a picture of my work incase you are confused