Not enough information to properly answer this... hope this helped though
Add 23 from both sides
6f = 18
F= 3
6(3)-23
= 18-23
=-5
Believe me
In the first one divide -3 by both sides and when you get an answer plug it back in for x to check and got second one multiple bu four on both sides and you will get an answer. And put that answer on the graph.