C=8h+12 the 8h represents the $8 per hour for renting the boat, and h represents however many hours you rent the boat for. The +12 is the initial $12 fee. This is in slope intercept form, just using different variables than y=mx+b
you replace the letter with the number given to replace them. So, in the equation you replace the letter C with -1, as it tell you on the side. You do the same with F, but with 3. your equation should look like: 7(-1 + 5) - 3 × 4. you then solve from there and should get 16. I hope this is right, if not my bad
