Answer:
B
Step:
The general equation for linear is y=mx+b
So all is linear except B

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 :)
The rate of change is -29/5x^2
Y=-5x+2
Y=mx+b
M=slope
B=y intercept