I’m not sure what the first one is, but number 4 is A) y=2x+4

As you've got 15%, the best thing to do is to find 10%, then multiply it by 1.5. Once you've found the tip, you add this onto the cost of the meal.
Therefore, the total cost of $25 meal with a 15% tip is $28.75
Hope this helps :)
Answer:
y= -7x+7
Step-by-step explanation:
y= mx+b
y= slope x+ y intercept